An Animal A Day
-
Dingo
The Dingo (Canis lupus dingo), is a type of wolf, probably descended from the Indian Wolf (Canis lupus pallipes). It is commonly described as an Australian wild dog, but is not restricted to Australia, nor did it originate there.
Dingo, Canis lupus dingo
The earliest known Dingo skulls have been found in Vietnam and are about 5,500 years old. Dingo remains from 5,000 to 2,500 years old have been found in other parts of South-east Asia, and the earliest record of Dingos in Australia is 3,500 years old.
The ultimate origin of the Dingo is uncertain, but it is clearly related to the wolves of south-west Asia, and probably arose in that area at about the same time as humans began to develop agriculture. Current thinking suggests that modern dogs are a mixture of several separate domestications of wolves at different times and in different areas: the modern Dingo appears to be a relatively pure-bred descendant of one of the earliest domestications. It is probable that 14,000 year-old Dingo-like bones found in Israel, and 9,000 year-old bones in the Americas are evidence of the commensal relationships that developed between wolves and people—as people migrated eastward, semi-domesticated dogs came with them. The Carolina dog found in the US southeast resembles the dingo and has common genetic features not found in other dogs.
Modern Dingos are found throughout South-east Asia, mostly in small pockets of remaining natural forest, and in mainland Australia, particularly in the north. They have features in common with both wolves and modern dogs, and are regarded as more-or-less unchanged descendants of an early ancestor of modern dogs.
At between 10 and 24 kilograms, Dingos are a little smaller than most wolves of the northern hemisphere (in keeping with Bergmann's Rule) and have a lean, athletic build. They stand between 44 and 63 cm high at the shoulder, and the head-body length varies between 86 and 122 cm. Colour varies but is usually ginger: some have a reddish tinge, others are more sandy yellow; the underside is lighter. Most Dingos have white markings on the chest, feet, and the tip of the tail; some have a blackish muzzle. (The one illustrated above is paler than usual, and noticeably more thick-set than most.)
Unlike domestic dogs, Dingos breed only once a year, do not bark, have permanently erect ears and are usually a sandy-peppered colour. They have a more independent temperament than dogs, and the skull is distinctive, with a narrower muzzle, larger auditory bullae, larger canine teeth, and a domed head.
Dingos did not arrive in Australia as companions of the original Aborigines around 50,000 years ago, but seem to have been brought by seafaring Austronesian traders at about the same time as the Great Pyramids were being built in ancient Egypt. A study of dingo mitochondrial DNA published in 2004 places their arrival at around 4000 BC, and suggests that only one small group may be the ancestors of all modern dingos.
The Dingo spread rapidly, probably with human assistance, and is thought to have occupied the entire continent within a short time. The full extent of the ecological change brought about by the introduction of the Dingo remains unknown, but there is little doubt that it was responsible for a series of extinctions, notably of marsupial carnivores, including the last remaining large predator, the Thylacine. (Note that the demise of the Australian megafauna took place more than 40,000 years before Dingos arrived and is believed to have been largely a result of human impact on an already fragile ecosystem.)
Aboriginal people across the continent adopted the Dingo as a companion animal, using it to assist with hunting, and for warmth on cold nights.
Wild Dingos prey on a variety of animals, mostly small or medium-sized, but also larger herbivores at need. Generally, Dingos live in small family groups, but they are capable of forming larger packs to hunt cooperatively. It is thought that this gave Dingos an important competitive advantage over the more solitary marsupial carnivores, particularly during Australia's frequent droughts (when game becomes scarce).
When European settlers first arrived in Australia, Dingos were tolerated, even welcomed at times. That changed rapidly when sheep became an important part of the white economy. Dingos were trapped, shot on sight, and poisoned—often regardless of whether they were truly wild or belonged to Aboriginal people. In the 1880s, construction of the great Dingo Fence began. The Dingo Fence was designed to keep Dingos out of the relatively fertile south-east part of the continent (where they had largely been exterminated) and protect the sheep flocks of southern Queensland. It would eventually stretch 8,500 kilometres; from near Toowoomba through thousands of miles of arid country to the Great Australian Bight and be (at that time) the longest man-made structure in the world. It was only partly successful: Dingos can still be found in parts of the southern states to this day, and although the fence helped reduce losses of sheep to predators, this was counterbalanced by increased pasture competition from rabbits and kangaroos.
Dingoes have received bad publicity in recent years as a result of the highly publicised Azaria Chamberlain disappearance and also because of Dingo attacks on Fraser Island in Queensland. They are opportunistic carnivores, taking prey ranging in size from lizards and small rodents up to sheep and kangaroos. Unlike many feral dogs, Dingoes do not generally form packs; they more often travel in pairs or small family groups. While Dingo groups use defined home territories, these territories can overlap with those of other groups.
As a result of interbreeding with dogs introduced by European settlers, the purebred Dingo gene pool is being swamped. By the early 1990s, about a third of all wild Dingos in the south-east of the continent were hybrids, and although the process of interbreeding is less advanced in more remote areas, the extinction of the subspecies in the wild is considered inevitable.
The Australian National Kennel Council recognises the Dingo as a pure breed of dog and accepts the breed for showing in those states where it is legal to own. Most other Kennel Clubs, including the international Federation Cynologique Internationale, do not recognise or register Dingos.
Conservation status: Secure
Issue #38 -
Zebu
Zebus (Bos taurus) are known as 'humped cattle' and are better-adapted to tropical environments than other domestic cattle. Their scientific name was originally Bos indicus, but this name is now deemed invalid by ITIS, who classify the zebu under Bos taurus along with all other domestic cattle. Zebus are descendants of aurochs domesticated in India about 10,000 years ago. The ancient species of Bos nomadicus cattle or even gaur may have contributed to the development of the zebus. There are some 75 known breeds, split about evenly between African breeds and South Asian ones. The major Zebu cattle breeds of the world include Gyr, Guzerat, Indu-Brazilian, Nellore, Ongole and Brahman.
Zebu, Bos taurus
Zebu have humps, large dewlaps and ears. They have more sweat glands than European cattle (Bos taurus). They handle hot, humid climates well and have pest resistances not seen in European cattle.
Because they were better adapted to hot environments, zebus were imported to Africa for thousands of years and interbred with native cattle there. Genetic analysis of African cattle has found higher concentrations of zebu genes all along the east coast of Africa, and especially pure cattle on the island of Madagascar, implying that the method of dispersal was cattle transported by ship. Partial resistance to rinderpest led to another increase in the frequency of zebus in Africa.
Zebu were imported into Brazil in the early twentieth century and crossbred to Charolais cattle, a European breed. The resulting breed, which consists of 5/8 Charolais and 3/8 Zebu is called the Chanchim. It has a better meat quality than the zebu but better heat resistance than European cattle. The zebu breeds used were primarily Indubrazil with some Nelore and Guzera.
Draft zebus in Mumbai, India
Numerous breeds are complex mixtures of the zebu and other Bos taurus varieties, and some also have yak, gaur or banteng genetics. While zebu are the common cattle in much of Asia, Japanese, Korean and Mongolian cattle are closer related to the European type.
Bulls from the Brahman breed of zebu are often used in for bullriding in rodeo.
The Zebu were also mentioned in the VeggieTales silly song, "The Song of the Cebu".
Issue #39 -
Kiwi
A kiwi is any of the species of small flightless birds native to New Zealand of the genus Apteryx (the only genus in family Apterygidae). At around the size of a domestic chicken, kiwi are by far the smallest living ratites. Though they are thought to be most closely related to either cassowaries or moa, their evolutionary origin is still uncertain. Several kiwi species are endangered. The kiwi is also a national symbol for New Zealand.
Kiwi, genus Apteryx
Prior to the arrival of humans in about 1300, New Zealand's only endemic mammals were two species of bat (the long-tailed bat (Chalinolobus) and the short-tailed bat (Mystacina)). The ecological niches that in other parts of the world were filled by creatures as diverse as horses, wolves and mice were taken up by birds (and, to a lesser extent, reptiles).
Kiwi are shy, nocturnal creatures with a highly developed sense of smell and, most unusual in a bird, nostrils at the end of their long, sharp bill. They feed by thrusting the bill into the ground in search of worms, insects, and other invertebrates; though they also take fruit and, if the opportunity arises, small crayfish, amphibians and eels.
Their adaptation to a terrestrial life is extensive: like all ratites they have no keel on the breastbone to anchor wing muscles, and barely any wings either: the vestiges are so small that they are invisible under the kiwi's bristly, hair-like, two-branched feathers. While birds generally have hollow bones to save weight and make flight practicable, kiwi have marrow, in the style of mammals. With no constraints on weight from flight requirements, some Brown Kiwi females carry and lay a single 450 gram egg.
Currently there are three accepted species, one of which has two sub-species:
-- The North Island Brown Kiwi, Apteryx australis mantelli is widespread in the northern two-thirds of the North Island and with about 35,000 remaining is the most common kiwi. Females stand about 400 mm high and weigh about 2.8 kg, the males about 2.2 kg. The North Island Brown has demonstrated a remarkable resilience: it adapts to a wide range of habitats, even non-native forests and some farmland. The plumage is streaky red-brown and spiky. The female usually lays two eggs, which are incubated by the male.
-- The Okarito Brown Kiwi, Apteryx australis australis, is a recently identified sub-species of the North Island Brown, slightly smaller, with a greyish tinge to the plumage and sometimes white facial feathers. Females lay as many as three eggs in a season, each one in a different nest. Male and female both incubate. These Kiwi are distributed in the South Island of New Zealand.
The distribution of Apteryx australis
Analysis of mitochondrial DNA, ecology, behavior, morphology, geographic distribution and parasites of the North Island Brown Kiwi has led scientists to propose that the North Island Brown Kiwi is three distinct species. The North Island Brown Kiwi, the Okarito Brown Kiwi, or Rowi, whose distribution is restricted to a single site on the West Coast of the South Island of New Zealand. A third distict population of the North Island Brown Kiwi is the Tokoeka, distributed in the in lowland forest to the north of Franz Josef glacier in the South Island. Reclassification would make five recognised kiwi species.
-- The largest species is the Great Spotted Kiwi, Apteryx haastii, which stands about 450 mm high and weighs about 3.3 kg. (Males about 2.4 kg) It has grey-brown plumage with lighter bands. The female lays just one egg, with both sexes incubating. Population is estimated to be over 20,000, distributed through the more mountainous parts of northwest Nelson, the northern West Coast, and the Southern Alps.
The distribution of Apteryx haastii
-- The very small Little Spotted Kiwi, Apteryx owenii is unable to survive predation by imported pigs, stoats and cats and is extinct on the mainland and the most threatened of all kiwi. About 1,000 remain on Kapiti Island and it has been introduced to other predator-free islands and appears to be becoming established. A docile bird the size of a bantam, it stands 250 mm high and the female weighs 1.3 kg. She lays one egg which is incubated by the male.
The distribution of Apteryx owenii
Conservation status: Vulnerable
Issue #40 -
Tuatara
The tuatara is the only surviving member of Rhynchocephalia (modernly known as either Sphenodontia or Sphenodontida), an order that has survived virtually unchanged for 200 million years. Tuataras are endemic to New Zealand, and now live only on a small number of offshore islands. It has been classified as an endangered species since 1895. Tuatara, like many native New Zealand animals, are threatened by habitat loss, harvesting, and introduced species such as mustelids and rats.
There are two extant species: Sphenodon punctatus and the much rarer Sphenodon guntheri, or Brothers Island tuatara which is confined to The Brothers Islands in Cook Strait. These have olive skin with yellowish patches.
Tuatara, Sphenodon punctatus
Though tuataras resemble lizards, the genus has several characteristics unique among reptiles. Its teeth are fused to its jaw bone; it has no external copulatory organs or earholes. Indeed, tuatara were originally classified as lizards in 1831 when the British Museum received a skull. The species remained misclassified until 1867, when Gunther (also at the British Museum) noted certain bird-like, turtle-like, and crocodile-like features and proposed the order Rhynchocephalia for the tuatara and its fossile relatives.
The name tuatara derives from the Maori language, meaning "spiny back". Tuatara feature in a number of indigenous legends. They are held as ariki (God forms). Tuatara are regarded as the messengers of Whiro, the god of death and disaster. Mâori women are forbidden to eat tuatara.
Tuatara thrive in much lower temperatures than are tolerated by most reptiles, preferring temperatures of 16–21°C (60–70°F); temperatures over 27°C (80°F) are fatal. Adults are about 50 cm long and weigh between 500 and 1,000 grams. Tuatara are notoriously cryptic, and hibernate in winter. Adults are terrestrial and nocturnal, but hatchlings are arboreal and diurnal (likely because the adults are known to eat younger tuatara).
Tuatara are extremely long-lived, with individuals commonly living for over a century. They reproduce very slowly: tuataras take at least ten years to reach sexual maturity, females only lay eggs once every four years, and it takes between 12 and 15 months after copulation for a new tuatara to hatch from its egg. The sex of the hatchling depends on the temperature of the egg, with warmer eggs tending to produce male tuatara, and cooler eggs producing females. Tuatara continue to grow larger for the first thirty-five years of their lives, and they can hold their breath for over an hour.
Like some lizards, the tuatara has a third eye on the top of its head. In adult animals, a scale grows over the eye, and its purpose is unknown. It may be useful in absorbing ultraviolet rays to manufacture vitamin D.
Issue #41 -
California Tiger Salamander
The California Tiger Salamander (Ambystoma californiense) is an endangered amphibian native to Northern California. Previously considered to be a Tiger Salamander subspecies, the California was recently designated a separate species.
California Tiger Salamander, Ambystoma californiense
Description
The California Tiger Salamander is a relatively large, secretive amphibian. Adults can grow to a length of about 19-20 cm (7-8 inches). It has a stocky body and a broad rounded snout. Adults are black and have yellow or cream spots; larvae are greenish-grey in color. The California Tiger Salamander has protruding eyes with black irises.
Habitat and range
The California Tiger Salamander is endemic to California. Because it depends on water for reproduction, its habitat is limited to the vicinity of large, fishless vernal pools or similar water bodies. It occurs at elevations up to 1,000 m (3,200 ft).
It occurs in California in Sonoma County and Santa Barbara County, in vernal pool complexes and isolated ponds along the Central Valley from Colusa County to Kern County, and in sag ponds in the coastal range. Both the Sonoma and Santa Barbara populations are listed as endangered since 2000 and 2003, respectively. The U.S. Fish and Wildlife Service is currently campaigning to list all the populations as threatened. The main threat to the salamanders is habitat destruction through human interaction.
The habitat includes Lake Lagunita at Stanford University, and the need to protect this site is a primary given reason for the cancellation of the Big Game bonfire.
Life cycle
Adults spend most of their lives underground, in burrows created by other animals such as ground squirrels: the salamanders themselves are poorly equipped for burrowing. Little is known about their underground life, except that they spend the dry season in estivation.
Breeding takes place in December, when the wet season allows the salamanders to migrate to the nearest pond, a journey that may be as far as a mile and take several days. The eggs, which the female lays in small clusters or singly, hatch after some 10 to 14 days.
The larval period lasts for three to six months. The larvae feed on other small invertebrates, including tadpoles. When their pond dries, they resorb their gills, develop lungs, and then the metamorphs leave the pond in search of a burrow.
California Tiger Salamanders are believed to have relatively long life spans, ten years or more.
Conservation status: Vulnerable
Issue #42 -
Black and yellow mud dauber
The black and yellow mud dauber (Sceliphron caementarium) is a type of wasp, and like most wasps is not particularly hostile (despite the common misconception, only social wasps - especially yellowjackets - tend towards aggressive). They are solitary insects that build small nests out of mud in or around homes, barns, and other structures.
Black and yellow mud dauber, Sceliphron caementarium
The black and yellow mud dauber's nest is comprised of a series of cylindrical cells that are plastered over to form a smooth nest about the size of a human fist. After building a nest, the female wasp captures several spiders or insects. The captured prey are stung and paralyzed before being placed in the nest, and then a single egg is deposited on the prey within each cell. The wasp then seals the cell with mud. After finishing a series of cells, she leaves and does not return. Eventually, the hatching larvae will eat the prey and emerge from the nest.
Mud daubers very rarely, if ever, sting people or animals. Even when thoroughly agitated or aroused, they are not likely to sting. Because of their calm tempers and ability to control the insect and spider population, many people respect them. In many rural areas of the southern United States, killing a mud dauber without reason is considered cruel and silly.
Issue #43 -
Ocean Sunfish
The Ocean Sunfish (Mola mola) is a bizarre pelagic fish, the largest bony fish in the world, with specimens observed up to 3.3 m in length and weighing up to 2,300 kg. A member of order Tetraodontiformes, it is the type species of its genus.
Ocean Sunfish, Mola mola
Ocean Sunfish are commonly mistaken for sharks, as they often swim close to the surface and have dorsal fins that stick up out of the water in a shark-like fashion. However, Ocean Sunfish feed on zooplankton (along with small fish and other marine life), and are commonly friendly towards people, such as divers who venture into their habitat. They are found in warm and temperate zones of all oceans, including the Eastern Pacific and the eastern and western Atlantic.
Unusually, Mola mola uses its long, thin dorsal and anal fins for propulsion; it lacks a caudal fin, having in its place a rudder-like structure, the clavus. Its fry resemble miniature pufferfish, a hint at the species's place in the evolutionary tree.
While the flesh of the Ocean Sunfish is considered a delicacy by some, it contains neurotoxins similar to those of other poisonous Tetraodontiformes.
The Ocean Sunfish is also known as the marine sunfish, the moon fish, or simply by its specific name, mola (Latin for "millstone", which it was said to resemble). It has various obsolete binomial synonyms; its original name was Tetraodon mola.
Sunfish eat comb-jellies, zooplankton, squid, and crustaceans. They live in the eastern pacific and atlantic.their predators are orcas, sea lions, dolphins and marlins. they are thought to live for over 10 years.
The freshwater sunfishes (family Centrarchidae) are unrelated.
Conservation status: Secure
Issue #44 -
Zebra mussel
The Zebra mussel (Dreissena polymorpha) is originally from southeast Russia.
Zebra mussel, Dreissena polymorpha
Reproduction
An adult female Zebra Mussel may produce between 30,000 to 100,000 eggs per year. Spawning usually begins in the months from late spring to early summer. The presence of food is the first factor that contributes to spawning. During this time a large population of algae will produce a pheromone recognized by Zebra Mussels. However, temperature is the main factor in determining when the spawning season begins. The ideal temperature for Zebra mussel is 12 degrees Celsius and higher for spawning to start. If by any chance that above condition does not apply, then spawning may be suspended by that population.
Spread
Zebra mussels have been spreading for a long time. In 1850 they were first seen in the Netherlands.
Zebra mussels are causing serious problems in North America where they are considered an invasive species. Zebra mussels were first detected in the Great Lakes in 1988 and have caused widespread damage in this formerly closed ecosystem. It is believed that they were inadvertently introduced into the lakes in the water ballast tanks of ocean going ships traversing the St. Lawrence Seaway.
From their first appearance in American waters in 1988 they have spread to a large number of waterways including the Mississippi and Hudson Rivers disrupting the ecosystem, killing the local unoinoida mussels, and damaging harbours, boats, and power plants, among others.
Ecology
Zebra mussels are voracious filter-feeding organisms. They remove particles from the water column increasing water clarity. Some particles are consumed as food, and feces are deposited on the lake floor. Non-food particles are combined with mucus and deposited on lake floors as pseudofeces.
Lake floor food supplies are enriched by zebra mussels. The additional organic material, coupled with increased habitat complexity results in increased density and diversity of benthic organisms.
Food
Zebra Mussels are edible, but most experts advise against eating any found in areas of pollution concern since zebra mussels accumulate contaminants and toxins from the water that they filter. As long as they come from a reasonably clean body of water, Zebra Mussels can be used in any recipe calling for mussels though they are quite small, so it would take a lot of them for most recipes.
Issue #45 -
Broad-faced Potoroo
The extinct Broad-faced Potoroo (Potorous platyops) was first collected in 1839 and described by John Gould in 1844, but even then it was rare and only a handful of specimens were ever collected, the last in 1875. Subfossil remains indicate that it originally had an extensive distribution from the semi-arid coastal districts of South Australia to the Western Australian coast, and possibly as far north as North West Cape.
Broad-faced Potoroo, Potorous platyops
The habits of the Broad-faced Potoroo are almost entirely unknown. It is clear that it avoided the fertile forested areas that its relatives the Long-nosed and Long-footed Potoroos inhabit. It is unusual amongst recently extinct Australian vertebrates in that it appears to have declined significantly before European settlement of Australia.
Preserved specimens indicate that it was smaller than the other potoroos at around 24 cm long with an 18 cm tail. The coat was grizzled grey above and dirty white below, the body similar in shape to that of a large rat. The ears were small and rounded, the muzzle fairly short, and the cheeks notably puffy.
Conservation status: Extinct (c. 1875)
Issue #46 -
Maine Coon
The Maine Coon is one of the largest breeds of domestic cat. The breed is a naturally occurring one from New England. Cold New England winters have made this cat very well adapted to cold weather. The name comes from a legend that a domestic cat released in the wilds of Maine interbred with a raccoon, resulting in offspring with the Maine Coon characteristics. Maine Coons resemble their European counterparts, the Norwegian Forest Cats.
Maine Coon
Physical characteristics
Maine Coons are very large, but energetic cats, often weighing over 10 kilograms (22 pounds). The most common color in the breed is tabby markings, but all coat colors exist. They have medium-long, dense fur, with longer hair, or ruff, on their chests and a pronounced mane, similar to a lion. Their fur consists of two layers, with an additional layer of guard hairs. The fur is generally very soft. They have long hair on the backs of their legs, and between their toes, to assist keeping warm while in the snow. Their tails are bushy. Their heads are broad, the males' heads being larger than females', with wide-set ears that have tufts of fur in them.
Behavioural characteristics
Maine Coons are intelligent, dextrous, and playful. They have a tendency to use their front paws extensively (often curling the paw round to pick things up) and as a consequence will easily learn to open cabinet doors or pick small objects up. In addition to this, Maine Coons have a tendency to use their paws to knock on a surface to gain entry, much like a human would. They'll do this with a motion similar to vertical wiping strokes (top-down) with enough force at contact to produce a sound. If left outside or in another room, for example, they may employ this method to gain their owner's attention. Some Maine Coons will eat with their paws, rather than eating from the bowl itself. They can also be trained to play fetch. They are very curious, and will explore anywhere and everywhere possible. They are happy to stay indoors, as long as they have an adequate amount of playtime and exercise. While being a lap cat depends on the individual cat's own personality, most do enjoy being near their people, other cats and even dogs. Maine Coons are generally very quiet, not tending to meow much, unless they are hungry. Maine Coons do make a very distinct sound, called trilling, that is soft and high-pitched, usually used when happy or startled. Some Maine Coons enjoy playing with, but not usually in, water. They may dip toys in their water bowls before playing with them, or just tip the water bowl over. They may also "fish" in their water bowl. A few have been known to hop in the shower with their owner. The males tend to be quite goofy, and a bit clumsy, but in a good-natured way. Maine Coons can occasionally be a bit mischievous when bored, such as deliberately pushing things off tables and the tops of fridges with their paws, to see what happens.
A Tabby-colored Maine Coon adult male (right) next to an average sized adult tortoiseshell mixed breed female.
Maine Coons have a tendency to be very independent - that is, they do not beg for attention as much as other breeds. As a result of this, they may encounter problems with another Maine Coon if it is not introduced into the household at the same time. Maine Coons can be described as the "king" of the house, having a tendency to keep other pets (cats and other species alike) in check at any given time. These cats will generally stand up to a dog many times their size, and "argue" with it.
Grooming and cleaning
Maine Coons need to be combed out once a week, to avoid mats in their fur, especially on their belly, in their armpits, and on the backs of their legs.
Country of origin: United States
Issue #47 -
Malayan Tapir
The Malayan Tapir (Tapirus indicus), also called the Asian Tapir, is the largest of the four species of tapir and the only one native to Asia. The scientific name is somewhat misleading, as the Tapirus indicus is not native to India.
Malayan Tapir, Tapirus indicus
General Appearance and Characteristics
The animal is easily identified by its markings, most notably the light-colored “saddle” which extends from its shoulders to its rump. The rest of its hair is black, except for the tips of its ears which, as with other tapirs, are rimmed with white. This pattern is for camouflage: the disrupted coloration makes it more difficult to recognize it as a tapir, and other animals may mistake it for a large rock rather than a form of prey when it is lying down to sleep.
Malayan Tapirs grow to between 6 and 8 feet (1.8 to 2.4 m) in length, stand 3 to 3.5 feet (90 to 107 cm) tall, and typically weigh between 550 and 700 pounds (250 to 320 kg), although they can weigh upwards of 900 pounds (410 kg) on occasion. The females are usually larger than the males. Like the other types of tapir, they have small stubby tails and long, flexible proboscises. They have four toes on each front foot and three toes on each back foot. The Malayan Tapir has rather poor eyesight but excellent hearing and sense of smell.
Lifecycle
The gestation period of the Malayan Tapir is approximately 400 days, after which a single offspring, weighing around 15 pounds (6.8 kg), is born. Young tapirs of all species have brown hair with white stripes and spots, a pattern with enables them to hide effectively in the dappled light of the forest. This baby coat fades into adult coloration between four and seven months after birth. Weaning occurs between between six and eight months of age, at which time the babies are nearly full-grown, and the animals reach sexual maturity around age three. Breeding typically occurs in April, May or June, and females generally produce one calf every two years. Malayan Tapirs can live up to 30 years, both in the wild and in zoos.
Behavior
Malayan Tapirs are primarily solitary creatures, marking out large tracts of land as their territory, though these areas usually overlap with those of other individuals. Tapirs mark out their territories by spraying urine on plants, and they often follow distinct paths which they have bulldozed through the undergrowth.
Exclusively vegetarian, the animal forages for the tender shoots and leaves of more than 100 species of plants (though it prefers around 30), moving slowly through the forest and pausing often to eat and note the scents left behind by other tapirs in the area. However, when threatened or frightened, the tapir can run quickly, despite its considerable bulk, and they can also defend themselves with their strong jaws and sharp teeth. Malayan Tapirs communicate with high-pitched squeaks and whistles. They usually prefer to live near water and often bathe and swim, and they are also able to climb steep slopes. Tapirs are mainly active at night, though they are not exclusively nocturnal. They tend to eat soon after sunset or before sunrise, and they will often nap in the middle of the night. This type of behavior characterizes them as crepuscular animals.
Habitat, Predation, and Vulnerability
The Malayan Tapir was once found throughout the tropical lowland rainforests of Southeast Asia, including Cambodia, Indonesia, Laos, Malaysia, Myanmar (Burma), Thailand, and Vietnam. Due to human activity, especially deforestation for agricultural purposes as well as poaching and illegal trade, its habitat and numbers have decreased in recent years and, like all tapirs, it is in danger of extinction.
Range of the Malayan Tapir
The species is officially recognized as “Vulnerable” under the 1996 IUCN Red List of Threatened Animals. The exact number of Malayan Tapirs left in the wild is unknown, but many scientists estimate that there are approximately 3,000 individuals left in the wild and 200 in zoos worldwide. Tapirs are rarely hunted by animals other than humans, because their tough skin and good defenses make it difficult to harm a healthy adult. Leopards and tigers may attack calves, old adults, or ill individuals, but for the most part the threat to tapirs comes from humans.
Conservation status: Vulnerable
Issue #48 -
Common Starling
The Common Starling (Sturnus vulgaris) is a passerine bird in the family Sturnidae.
An immature female Common Starling, Sturnus vulgaris, in London
This starling is native to most of Eurasia, but has been introduced to South Africa, North America, Australia and New Zealand. This adaptable and omnivorous species has proved to be a pest in several of these countries. In Western Australia, which is starling-free, the government pays full-time hunters to patrol the border and shoot starlings as they arrive.
It is resident in southern and western Europe, but migrates from colder regions to these areas, and further south to Iberia (where it does not breed) and north Africa.
The Starling is catholic in its choice of habitats, and can be found in any reasonable open environment from farmland to saltmarsh.
These birds will eat almost anything, including farmland invertebrates and berries. This is a highly gregarious species, forming huge flocks in winter, and providing a spectacular sight as they descend into evening reed-bed roosts, often attracting birds of prey. Large roosts (exceptionally up to a million birds) can form in city centres, causing a great deal of mess from their droppings.
This is a hole-nesting species, and has impacted on native species where it has been introduced because of competition for nest sites.
This must be one of the most familiar of birds, with its shiny black plumage spangled with white. Confusion is only likely in Iberia in winter, when it has to be distinguished from the closely related Spotless Starling, which, as its name implies, has less spotting on its plumage. Adult males are less spotted below than adult females. Juveniles are dull brown, and by their first winter resemble adults but are browner especially on the head.
Starlings walk rather than hop. Their flight is quite strong and direct; they look triangular-winged and short-tailed in flight. In most of Europe, only the rarer and much paler Bohemian Waxwing shares this flight profile. This is a noisy bird, and a good mimic, like many of its family. In captivity, they are gregarious and love to imitate all types of sounds and speech, earning them the nickname "Poor-man's Myna". Information on care of Starlings as well as recordings of a Starling talking can be found at Starling Central.
Although there are approximately 200 million starlings in North America, they are all descendants of approximately 100 birds released in Central Park in the 1890s from Europeans. These starlings have created an evolutionary problem in North America since the starling prey has not adapted any type of defense instincts. This is what makes the European Starlings severely overpopulated and the birds can now be found all through North America and Alaska.
Issue #49 -
American Crocodile
The American Crocodile (Crocodylus acutus) is the only New World crocodile and the top predator in its range.
American Crocodile, Crocodylus acutus, at Ding Darling reserve, Sanibel Island, Florida
Like all crocodiles it is a quadruped, with four short, splayed legs; a long, powerful tail; a scaly hide with rows of ossified scutes running down its back and tail; and mighty jaws. It has nictitating membranes to protect its eyes, and, despite the myths it does have lachyrmal glands, and can cleanse its eyes with tears.
The nostrils, eyes, and ears are situated on the top of its head, so the rest of the body can remain concealed underwater. The coloration also helps them hide.
American Crocodiles normally crawl along on their belly, but they can also "high walk". Smaller specimens can gallop, and even larger crocodiles are capable of surprising bursts of speed. They can swim equally fast by moving their body and tail in a sinuous fashion, but they can sustain this form of movement much longer.
They have a four-chambered heart, like a bird, which is especially efficient at oxygenating their blood. They normally dive for only a couple of minutes, but will stay underwater for up to 30 minutes if threatened, and if they remain inactive they can hold their breath for up to 2 hours. They have an ectothermic metabolism, so they can survive a long time between meals — though when they do eat, they can eat up to half their body weight at a time.
Issue #50 -
Leopard frog
Leopard frogs, which are also called meadow frogs and grass frogs, are a collection of so-called true frogs within the genus Rana. Once abundant in North America and Canada, their population has declined in recent years due to pollution and deforestation. Leopard frogs are often used as environmental indicator species because of their heightened sensitivity to chemical pollutants found in the air and water and are commonly used as dissection specimens in biology classrooms.
Green leopard frog, genus Rana, in a swamp with duckweed
Leopard frogs are recognized by their green or brown coloration with distinct light-edged dark spots across the back and pure white underside. They also have a characteristic line of raised glandular skin, called the dorsolateral ridge, extending from each eye to the groin. Some species also have a light marking on the center of their tympanic membrane. Males have two vocal sacs, located on both sides of the body, used to attract mates and establish territory. The adult ranges in size from about 5-11 cm (2-5 in) in length, depending on the species, with females generally larger than males.
Northern leopard frog
During mating season, the female lays 3,000-6,000 eggs, with each egg approximately 1.7 mm in diameter, in a large, flattened mass just below water surface. These eggs will attach to the pond substrate and one month after the eggs are laid, tadpoles emerge approximately 65-83 mm in length. The leopard frog will reach sexual maturity 2-3 years after eggs are laid and have a lifespan of 6-9 years.
Species of Leopard Frog
Rana berlandieri
Rana blairi
Rana chiricahuensis
Rana fisheri
Rana onca
Rana pipiens
Rana sphenocephala
Rana subaquavocalis
Rana yavapaiensis
Issue #51 -
Magicicada
Magicicada is the genus of the 13- and 17-year periodical cicadas of eastern North America. These insects display a unique combination of long life cycles, periodicity, and mass emergences. They sometimes go by the common name "seventeen-year locust", but they are not locusts at all; locusts belong to the order Orthoptera.
A 17-year Periodical cicada
Taxonomy
There are seven recognized species. Three species have a 17-year cycle:
- M. cassini (Linnaeus, 1758)
- M. septendecim (Fisher)
- M. septendecula (Alexander and Moore, 1962)
Four more species follow a 13-year cycle:
- M. neotredecim (Marshall and Cooley, 2000)
- M. tredecim (Walsh and Riley, 1868)
- M. tredecassini (Alexander and Moore, 1962)
- M. tredecula (Alexander and Moore, 1962)
Generally, the 17-year cicadas are distributed more in the northern states of the eastern United States, while the 13-year cicadas occur in the southern states.
Description
Periodical cicadas are slightly smaller than other, annual cicadas. Imagines have a size of 2.5 to 3 cm (1 to 1.2 inches). They are black, with red eyes and yellow or orange stripes on the underside. The wings are translucent and have orange veins.
Magicicadas (both teneral and fully developed).
They are harmless animals; they neither bite nor sting. They are not poisonous, and there is no evidence that they transmit diseases. They generally do not pose a threat to vegetation, but young plants may be damaged by excessive feeding or egg laying. It is thus advised not to plant new trees or shrubs just before an emergence of the periodical cicadas. Mature plants usually do not suffer lasting damage even by a mass-emergence.
Broods
Periodical cicadas are grouped into thirty broods, based on the year they emerge. Broods are numbered using Roman numerals; broods I-XVII are the seventeen-year cicadas, while broods XVIII-XXX are the thirteen-year cicadas. Some broods are not known to exist, but they are retained in the numbering scheme for convenience.
Brood IX emerged in 2003. Brood X, a seventeen year brood stretching from New York to North Carolina on the East Coast to Illinois and Michigan, emerged in May 2004. Brood X is the largest of the broods of the periodical cicadas. No broods are expected to emerge in 2005 or 2006. The next brood to emerge is Brood XIII -- the Northern Illinois Brood. After a seventeen-year hiatus, this brood is scheduled to emerge in 2007.
The next thirteen-year brood to emerge will be Brood XIX in 2011 in Maryland and Virginia.
Brood VII is an isolated population in upstate New York and consists only of M. septendecim. It emerged in 2001, and hence its next emergence will be in 2018.
Life Cycle
The nymphs of the periodical cicadas live underground, at depths of 30 cm (one foot) or more, feeding on the juices of plant roots. They stay immobile and go through five development stages before constructing an exit tunnel in the spring of their 13th or 17th year. These exit tunnels have a diameter of about 1-1.5 cm (½ in.)
Emergence holes
The nymphs emerge at an evening when the soil temperature is above 17°C (63 F) and climb to a suitable place on the nearby vegetation to complete their transformation into an adult cicada. They molt one last time and then spend about six days in the leaves waiting for their exoskeleton to harden completely. Just after this final molt, the teneral adults are white, but darken within an hour.
Magicicadas molting
The nymphs emerge in large numbers at about the same time, sometimes more than one million individuals per acre (250/m²). Their mass-emergence is a survival trait called "predator satiation": for the first week after emergence, the periodic cicadas are an easy prey for reptiles, birds, squirrels, cats, and other small and large mammals. The cicadas' survival strategy is simply to overwhelm predators by their sheer numbers, ensuring the survival of most of the individuals and thus of the species.
Adult periodical cicadas live only for a few weeks—by mid-July, they'll all be gone. Their short life has one sole purpose: reproduction. The males "sing" a mating song; like other cicadas, they produce loud sounds using their tymbal. The sounds of a "chorus"—a group of males—can be deafening and reach 100 dB.
After mating, the male weakens and dies. The female lives a little longer in order to lay eggs: it makes between six and 20 V-shaped slits in the bark of young twigs and deposits up to 600 eggs there. Shortly afterwards, the female also dies. After about six to ten weeks, the eggs hatch and the newborn nymphs drop to the ground, where they burrow and begin another 13 or 17-year cycle.
Magicicadas egg slits (circled in red)
Issue #52 -
Silver Dollar
The Silver Dollar (Metynnis argenteus, Ahl 1923) is a tropical fish belonging to the Characidae family which is closely related to the Pirahna. Originating in the Tapajós River basin in South America, this somewhat round-shaped silver fish with slight red-tinged anal fin is mostly found in tanks kept by fish keeping hobbyists. It will grow to a maximum length of 5.5 inches (14.0 centimeters).
Silver Dollar, Metynnis argenteus
The Silver Dollar is a peaceful schooling species that spends most of its time in the mid- to upper-level of the water. Its maximum lifespan is more than 10 years. An egg-layer, the adult fish will spawn around 2,000 eggs. This breeding occurs in soft, warm water in low light.
Silver Dollars natively live in a tropical climate in the sides of weedy rivers. They prefer water with a 5.0-7.0 pH, a water hardness of up to 15.0 dGH, and an ideal temperature range of 75-82 °F (24-28 °C). Their diet is almost exclusively vegetarian and in captivity they will often eat all the plants in a tank. They will also eat worms and small insects.
Conservation status: Unknown
Issue #53 -
Vampire Squid
The vampire squid (Vampyroteuthis infernalis), lit. "vampire squid from hell", is a small, deep-sea cirrate (finned) cephalopod found throughout the temperate and tropical oceans of the world. Unique retractile sensory filaments justify the vampire squid's placement in its own order of Vampyromorphida (formerly Vampyromorpha), sharing similarities with both squid and octopuses. As a phylogenetic relic it is the only surviving member of its order, first described and mistakenly identified as an octopus in 1903 by German teuthologist Carl Chun.
A Vampire Squid, Vampyroteuthis infernalis, drawn by Carl Chun, 1903.
Physical description
At a maximum 30 cm (1 foot) in total length, the vampire squid is of no threat to humans. Its 15 cm (6 inch) gelatinous body appears velvety jet-black, red, purple or brown, depending on location and lighting conditions. A webbing of skin connects its eight arms, each lined with rows of fleshy spines or cirri. Only the distal half (farthest from the body) of the arms have suckers. Its limpid, globular eyes—which appear red or blue, also depending on lighting—are proportionately the largest in the animal kingdom at 2.5 cm (1 inch) in diameter.
Mature adults have a pair of ear-like fins projecting from the lateral sides of the mantle. These fins serve as the adult's primary means of propulsion: vampire squid are said to "fly" through the water by way of flapping their fins. Their powerful beak-like jaws are as white as ivory. Within the webbing are two pouches wherein the tactile velar filaments are concealed. The filaments are analogous to a true squid's tentacles, extending well past the arms.
The vampire squid is covered entirely in light-producing organs called photophores. The animal has great control over the organs, capable of producing disorienting flashes of light for fractions of a second to several minutes in duration. The intensity and size of the photophores can also be modulated. Appearing as small white discs, the photophores are larger and more complex at the tips of the arms and at the base of the two fins, but are absent from the underside of the caped arms.
The chromatophores (pigment organs) common to most cephalopods are poorly developed in vampire squid. While this means the animal is not capable of changing their skin colour in the dramatic fashion of shallow-dwelling cephalopods, such trickery is not needed at the pitch black depths in which it lives.
Habitat and adaptations
The vampire squid is an extreme example of a deep-sea cephalopod, thought to reside at aphotic (lightless) depths from 600-900 metres (2,000-3,000 feet) or more. Within this region of the world's oceans is a discrete habitat known as the oxygen minimum zone (OMZ). Within the OMZ oxygen saturation is too low to support aerobic metabolism in most higher organisms. Nonetheless, the vampire squid is able to live and breathe normally in the OMZ at oxygen saturations as low as 3%; a feat no other cephalopod—and few other animals—can claim.
In order to cope with life in the suffocating depths, vampire squid have developed several radical adaptations. Of all deep-sea cephalopods, their mass-specific metabolic rate is the lowest. Their blue blood's hemocyanin binds and transports oxygen most efficiently, aided by gills with especially large surface area. The animals have weak musculature but maintain agility and buoyancy with little effort thanks to sophisticated statocysts (balancing organs akin to a human's inner ear) and ammonium-rich gelatinous tissues closely matching the density of the surrounding seawater.
At the shallower end of the vampire squid's vertical range, the view from below is like the sky at twilight: The highly sensitive eyes of deepwater denizens are able to distinguish the silhouettes of other animals moving overhead. To combat this, the vampire squid generates its own bluish light (bioluminescence) in a strategy called counterillumination: The light diffuses the animal's silhouette, effectively "cloaking" its presence from the watchful eyes below. Its own large eyes detect even the faintest of gleams. A pair of photoreceptors are located atop its head, perhaps alerting the animal to movements above.
Like other deep-sea cephalopods, vampire squid lack ink sacs. If threatened, instead of ink, a sticky cloud of bioluminescent mucus containing innumerable orbs of blue light is ejected from the arm tips. This luminous barrage, which may last nearly 10 minutes, is presumably meant to daze would-be predators and allow the vampire squid to disappear into the blackness without the need to swim far. The display is made only if the animal is very agitated; regenerating the mucus is costly.
Issue #54 -
Vampire Squid - Cont'd
Development
Few specifics are known regarding the ontogeny of the vampire squid. Their development progresses through three morphologic forms: the very young animals have a single pair of fins, an intermediate form has two pairs, and the mature form again has one. As the animals grow and their surface area to volume ratio drops, the fins are resized and repositioned in order to maximize gait efficiency. Whereas the young propel themselves primarily by jet propulsion, mature adults find flapping their fins to be the most efficient means. This unique ontogeny caused confusion in the past, with the varying forms identified as several species in distinct families.
If hypotheses may be drawn from knowledge of other deep-sea cephalopods, the vampire squid likely reproduces slowly by way of a small number of large eggs. Growth is slow as nutrients are not abundant at depths frequented by the animals. The vastness of their habitat and its sparse population make procreative encounters a fortuitous event. The female may store a male's hydraulically implanted spermatophore (a sort of tapered, cylindrical satchel of sperm) for long periods before she is ready to fertilize her eggs. Once she does, she may need to brood over them for up to 400 days before they hatch. The female will not eat towards this culmination and dies shortly thereafter.
Hatchlings are c. 8 mm in length and are well-developed miniatures of the adults, with some differences. Their arms lack webbing, their eyes are smaller and their velar filaments are not fully formed. The hatchlings are transparent and survive on a generous internal yolk for an unknown period before they begin to actively feed. The smaller animals frequent much deeper waters, perhaps feeding on marine snow (falling organic detritus).
Behaviour
What behavioural data known has been gleaned from ephemeral encounters with ROVs; animals are often damaged during capture and survive for no more than about two months in aquaria. An artificial environment makes reliable observation of non-defensive behaviour difficult.
With their long velar filaments deployed, vampire squid have been observed drifting along in the deep, black ocean currents. If the filaments contact an entity, or if vibrations impinge upon them, the animals investigate with rapid acrobatic movements. They are capable of swimming at speeds equivalent to two body lengths per second, with an acceleration time of five seconds. However, their weak muscles limit stamina considerably.
Unlike their deep-sea relatives, cephalopods living in more hospitable climes can afford to expend energy in protracted flight. Vampire squid must use innovative predator avoidance tactics in order to conserve energy. Their aforementioned bioluminescent "fireworks" are combined with the writhing of glowing arms, erratic movements and escape trajectories, making it difficult for a predator to home in.
In a threat response called "pumpkin posture," the vampire squid inverts its caped arms back over the body, presenting an ostensibly larger form covered in unappetizing spines. The underside of the cape is heavily pigmented, masking most of the body's photophores. The glowing arm tips are clustered together far above the animal's head, diverting attack away from critical areas. If a predator were to bite off an arm tip, the vampire squid can regenerate it.
Copepods, prawns and cnidarians have all been reported as prey of vampire squid. Little else is known regarding their feeding habits, but considering their environment, a fussy palate is unlikely. Vampire squid have been found among the stomach contents of large deepwater fish, deep diving whales and pinnipeds such as sea lions.
Fins look like ears (top) on the "vampire squid from hell." For defence, jagged arms fold back like a skirt.
A live Vampire Squid recently collected from the deep-sea (around 700 meters) off southern California (Pt. Conception) using a modified opening-closing tucker trawl with a thermally-insulated cod-end. The animal shows some evidence of skin damage. The lobed fins characteristic of this species are clearly visible. Note also the "velar filaments", which are modified dorsolateral arms, and the photophores. This photograph, taken on board a ship in a small aquarium, appears on the cover of the Journal of Experimental Biology 201(16), 1998.
Issue #54 -
Great Auk
At 75 centimetres or 30 inches, the flightless Great Auk (Pinguinus impennis) was the largest of the auks. It was hunted for food and down for mattresses from at least the 8th century. It is classified as the only species in the genus Pinguinus.
Great Auk, Pinguinus impennis
The Great Auk was once to be found in great numbers on islands off eastern Canada, Greenland, Iceland, Norway, Ireland and Britain, but it was eventually hunted to extinction. The last pair was killed July 3, 1844 on the island of Eldey off Iceland, though a later sighting was claimed of a live individual in 1852 off the Newfoundland Banks in Canada.
They were excellent swimmers, using their wings to swim underwater. Unlike other auks, however, the Great Auk could not fly, which is what made it so vulnerable to humans. The Great Auk laid only one egg each year.
One theory connects the Great Auk with the origin of the word penguin, which may have come from the Welsh phrase pen gwyn, meaning "white head", referring originally to the Great Auk. (Although the head of the Great Auk is not in fact white, there is a white patch behind the beak.) Later, when explorers discovered apparently similar birds in the southern hemisphere, what we now call penguins, the term was supposedly transferred to them. An alternative theory, suggested by John Latham in 1785, claims that the word penguin comes from the Latin pinguis meaning "fat", referring to the plump appearance of the bird.
Conservation status: Extinct (1844)
Issue #55 -
American Cocker Spaniel
The American Cocker Spaniel evolved in the United States from spaniels imported from Great Britain. The name cocker comes from the fact that the breed originally hunted woodcock. In the United States the breed is registered under the name "Cocker Spaniel", as is the English Cocker Spaniel in the UK, which can cause confusion between these two breeds. By the 1930s the American variety had become so different from its English ancestors that it was given separate breed status. Originally a gun dog, the Cocker now fulfills the position of family pet or show dog most often and is rarely seen hunting. He is a faithful and responsible children's companion. Cockers have been a highly popular American breed since the 1940s, occupying the top position in number of American Kennel Club registrations in many years.
American Cocker Spaniel
Appearance
American Cockers weigh 24 to 28 pounds (11 to 12.75 kg) and stand 15 inches (38 cm) maximum height. They come in three major colour varieties: black, ASCOB (Any Solid Color Other than Black) and particolor. The other solid colours are chocolate, red, buff, cream, and sable. The domed head, large dark expressive eyes, short deep muzzle, and abrupt stop are characteristic breed points. The coat is flowing, long, silky and abundant. The long, luxuriantly feathered ears are a striking breed feature.
Temperament
Their temperament is typically happy, trusting, and intelligent. However, their popularity also led to considerable bad breeding in an attempt to keep up with the demand, and some lines contain dogs who tend to be high strung and snappish. As with all puppies, owners are advised to choose their breeder carefully.
Health
Cocker Spaniels are susceptible to a variety of maladies, particularly infections, affecting their ears and, in some cases, their eyes. As a result, they may require more medical attention than some other breeds.
History
The name cocker comes from the fact that the breed originally hunted woodcock. In the United States the breed is registered under the name "Cocker Spaniel", as is the English Cocker Spaniel in the UK, which can cause confusion between these two breeds. By the 1930s the American variety had become so different from its English ancestors that it was given separate breed status. Originally a gun dog, the Cocker now fulfills the position of family pet or show dog most often and is rarely seen hunting. He is a faithful and responsible children's companion. Cockers have been a highly popular American breed since the 1940s, occupying the top position in number of American Kennel Club registrations in many years.
Alternative name: Cocker Spaniel
Country of origin: United States
Issue #56 -
Orangutan
Orangutans (also spelled orang utan, orang-utan, sometimes incorrectly orangutang) are two species of great apes with long arms and reddish, sometimes brown, hair native to Malaysia and Indonesia. The word orangutan is derived from the Malay orang hutan meaning man of the forest. They are the only extant species in the genus Pongo and the subfamily Ponginae, although that subfamily also includes the extinct Gigantopithecus and Sivapithecus genera.
An orangutan, genus Pongo
Orangutans are the most arboreal of the great apes, spending nearly all of their time in the trees. They are only found in rainforests on the islands of Borneo and Sumatra. These two small isolated populations were classified as subspecies until recently, when they were elevated to full specific level (Pongo pygmaeus on Borneo, and P. abelii on Sumatra). Furthermore, primatologists now recognise three subspecies of the Bornean orangutan: P. p. pygmaeus in northwest Borneo, P. p. morio in northeast and east Borneo, and P. p. wurmbii in southwest Borneo.
Orangutans are highly endangered in the wild. Orangutan habitat destruction due to logging, mining and forest fires has been increasing rapidly in the last decade. Much of this activity is illegal, occurring in national parks that are officially off limits to loggers, miners and plantation development. There is also a major problem with the illegal trapping of baby orangutans for sale into the pet trade; the trappers usually kill the mother to steal the baby.
Like the other great apes, orangutans are remarkably intelligent. In the mid-1990s, one population of orangutans was found to use feeding tools regularly. Evidence of this had been earlier discovered among chimpanzees by Jane Goodall in the 1960s. A 2003 paper in the journal Science described the evidence for distinct orangutan cultures (see link). Orangutans are generally among the least aggressive among the apes, being friendly animals. Particularly notable is that wild orangutans are known to visit human-run facilities for orphaned young orangutans released from illegal captivity, interacting with the orphans and probably helping them adapt in their return to living in the wild.
Major conservation centres in Borneo include those at Semenggok in Sarawak, and Sepilok near Sandakan in Sabah.
Conservation status: Endangered
Issue #57 -
Eurasian Eagle Owl
The Eurasian Eagle Owl (Bubo bubo) is a species of horned owl resident in much of Europe and Asia.
Eurasian Eagle Owl, Bubo bubo
The horned owls are a part of the larger grouping of owls known as the typical owls, Strigidae, which contains most species of owl. The other grouping is the barn owls, Tytonidae.
The Eagle Owl is a very large and powerful bird, larger than a Buzzard. It is 59-73 cm long with a 138-170 cm wingspan. It is capable of killing large prey items such as hares, crows and gulls.
It is largely nocturnal, and is found in mountains and forests with cliffs and rocky areas. It usually nests on cliff ledges.
The size, ear tufts and orange eyes make this a very distinctive species. It has a strong direct flight.
The Eagle Owl's scientific name comes from its deep booming call.
Eagle Owl at Combe Martin Wildlife and Dinosaur Park, North Devon, England.
Issue #58 -
Galápagos tortoise
The Galápagos tortoise (or giant Galápagos tortoise), Geochelone nigra, is the largest living tortoise. It can weigh over 225 kg (500 pounds) and measure 1.8 m (6 feet) from head to tail. It is a very slow-moving animal, moving only 0.25 km/h (0.16 miles per hour). It is a herbivore, eating grasses, plant leaves, cactus and fruits.
Galápagos tortoise, Geochelone nigra
The Galápagos tortoise has a very large shell (or carapace) made of bone. The shape of the carapace and other morphological features are indicative of the terrain the animal inhabits. Highland areas with lush vegetation near the ground are normally home to tortoises with domed shells; these animals have restricted upward head movement due to shorter necks, and tend to have shorter limbs as well (see photo). Coastal regions with less vegetation at ground level are inhabited by tortoises with saddle-back shells; their extended necks and limbs help them to reach food higher off the ground. Shells can also be of intermediate type, with characteristics between domed and saddle-back types.
The Galápagos tortoise is found on the Galápagos Islands just west of Ecuador in South America. Because of the 250,000 tortoises that inhabited the island, Spanish explorers named the islands Galápagos for the giant tortoises. Today only 15,000 are left.
One of the oldest living specimens is a giant Galápagos tortoise named Harriet in the Australia Zoo at Beerwah, Queensland, Australia. Its estimated date of birth is 1830.
Conservation status: Vulnerable
Issue #59 -
Caecilian
The Caecilians are an order (Gymnophiona or Apoda) of amphibians which resemble worms or snakes. They mostly live hidden in the ground which makes them the least explored order of amphibians, and widely unknown.
Caecilian, order Gymnophiona or Apoda
Anatomy
Caecilians' feet have degenerated, making the smaller species resemble worms, while the larger species with lengths up to 1.5 m resemble snakes. The tail is also very short, so the cloaca is near the end of the body. Their skin is smooth and usually dark-matt, but many species also have colorful skins. Inside the skin are calcite scales, which suggests that they are related with the fossil Stegocephalia. However the scales are now believed to be a secondary development, and not directly inherited from Stegocephalia. Due to their underground life the eyes are small and covered by skin for protection, which have led to the misconception that they are blind. However due to the skin cover their visual sense is limited to simple dark-light perception. All Caecilians share two tentacles at their head, which are probably used for the olfactory sense additional to the normal nose.
Except one lungless species - Typhlonectes eiselti, only known from one specimen collected somewhere in South America - all Caecilians have lungs, but also use the skin or the mouth for oxygen absorption. Often the left lung is much smaller than the right one, an adaptation to the body shape also found in snakes.
Distribution
Caecilians are found in most of the tropic areas of South-East Asia, Africa and South America, except the dry areas and the high mountains. In South America their distribution extends well into the temperate north of Argentina. For central Africa no systematic search has been done yet, but it is likely Caecilians are found all over the tropical rainforest there.
Reproduction
Caecilians are the only order of amphibians which only use internal insemination. The male Caecilians have a penis-like organ, the phallodeum, which is inserted into the cloaca of the female for 2 to 3 hours. About 25% of the species are oviparous; the eggs are guarded by the female. For some species the young Caecilians are already metamorphed when they hatch, other hatch as larvae. The larvae aren't fully aquatic, but spend the daytime in the soil near the water.
75% of the species are viviparous, that means they give birth to already developed offspring. The fetus is fed inside the female with special cells of the oviduct, which are eaten by the fetus with special scraping teeth.
Origin of the name
The name Caecilian derives from the Latin word caecus = blind, referring to the small or sometimes non-existing eyes. The name dates back to the taxonomic name of the first species described by Carolus Linnaeus, which he gave the name Caecilia tentaculata. The taxonomic name of the order derives from the Greek words gymnos = naked and ophio = snake, as the Caecilians were originally thought to be related with snakes.
Taxonomy
Taxonomically the Caecilians are divided into 5 families. The species numbers have to be taken with care, as many of the species are described after only one specimen. Probably not all species have been described yet, however some of the described different species might turn out to be normal variations inside one species.
- Beaked Caecilians (Rhinatrematidae) - 2 genera, 9 species
- Fish Caecilians (Ichthyophiidae) - 2 genera, 39 species
- Indian Caecilians (Uraeotyphlidae) - 1 genus, 5 species
- Tropical Caecilians (Scolecomorphidae) - 2 genera, 6 species
- Common Caecilians (Caeciliidae) - 26 genera, 107 species
Miscellany
Large Caecilians dubbed "ingots" plagued the French occupation of Indochina in the years before the Vietnam war. The creatures were reported to borrow large holes and disrupt troop movement.
Issue #60 -
Flea
Flea is the common name for any of the small wingless insects of the order Siphonaptera. Fleas are external parasites, living off the blood of mammals and birds.
Scanning Electron Micrograph of a Flea, order Siphonaptera
Some well known flea species include:
- Cat Flea (Ctenocephalides felis),
- Dog Flea (Ctenocephalides canis),
- Northern Rat Flea (Nosopsyllus fasciatus),
- Oriental Rat Flea (Xenopsylla cheopis).
In most cases fleas are just a nuisance to their hosts, but some people and some animals suffer allergic reactions to flea saliva resulting in rashes. Flea bites generally result in the formation of a slightly-raised swollen itching spot with a single puncture point at the center.
However, fleas can transmit disease. One devastating example of this was the bubonic plague, transmitted between rodents and humans. Murine typhus (endemic typhus) fever, and in some cases tapeworms can also be transmitted by fleas.
Life Cycle
Fleas pass through a complete life cycle consisting of egg, larva, pupa and adult. Completion of the life cycle from egg to adult varies from two weeks to eight months depending on the temperature, humidity, food, and species. Normally after a blood meal, the female flea lays about 15 to 20 eggs per day – up to 600 in its lifetime – usually on the host (dogs, cats, rats, rabbits, mice, squirrels, chipmunks, raccoons, opossums, foxes, chickens, humans, etc.). Eggs loosely laid in the hair coat drop out almost anywhere, especially where the host rests, sleeps or nests (rugs, carpets, upholstered furniture, cat or dog boxes, kennels, sand boxes, etc.).
Greyscale picture of Robert Hooke's drawing of a flea in his Micrographia.
Eggs hatch between two days to two weeks into larvae found indoors in floor cracks, crevices, along baseboards, under rug edges and in furniture or beds. Outdoor development occurs in sandy gravel soils (moist sand boxes, dirt crawlspace under the house, under shrubs, etc.) where the host may rest or sleep. Sand and gravel are very suitable for larval development which is the reason fleas are erroneously called "sand fleas."
Larvae are blind, avoid light, pass through three larval instars and take a week to several months to develop. Their food consists of digested blood from adult flea feces, dead skin, hair, feathers, and other organic debris; larvae do not suck blood. Pupae mature to adulthood within a silken cocoon woven by the larva to which pet hair, carpet fiber, dust, grass cuttings, and other debris adheres. In about five to fourteen days, adult fleas emerge or may remain resting in the cocoon until the detection of vibration (pet and people movement), pressure (host animal lying down on them), heat, noise, or carbon dioxide (meaning a potential blood source is near). Most fleas overwinter in the larval or pupal stage with survival and growth best during warm, moist winters and spring.
Flea bites can be treated with Calamine Lotion.
Families
Tungidae - Sticktight and Chigoe fleas
Pulicidae - Common fleas
Coptopsyllidae
Vermipsyllidae - Carnivore fleas
Rhopalopsyllidae - Marsupial fleas
Hypsophthalmidae
Stephanocircidae
Pygiopsyllidae
Hystrichopsyllidae - Rat and mouse fleas
Leptopsyllidae - Bird and rabbit fleas
Ischnopsyllidae - Bat fleas
Ceratophyllidae
Amphipsyllidae
Malacopsyllidae
Dolichopsyllidae - Rodent fleas
Ctenopsyllidae
Issue #61
