An Animal A Day

last SG · 2005-03-09T00:11:15+00:00

Deepwater Arrowtooth Eel The Deepwater Arrowtooth Eel (Histiobranchus bathybius) is a cutthroat eel of the genus Histiobranchus, found around the world at d...

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Anise Swallowtail

The Anise Swallowtail, Papilio zelicaon, is a common swallowtail butterfly of western North America. Both the upper and lower sides of its wings are black, but the upper wing has a broad yellow stripe across it, which gives the butterfly an overall yellow appearance. There are striking blue spots on the rear edge of the rear wing, and the characteristic tails of the swallowtails. Its wingspan is 7-9 cm. Its body is somewhat shorter than the rather similar Western Tiger Swallowtail, with which its range overlaps; it also lacks the black stripes, converging towards the tail, of the latter. There is a somewhat darker subspecies, Papilio zelicaon nitra, which is rare throughout the range, though somewhat more often found at lower elevations.

Anise Swallowtail, Papilio zelicaon, on the San Francisco Bay Trail in Tiburon, California

The Anise Swallowtail is a butterfly of fairly open country, and is most likely to be seen on bare hills or mountains, in fields or at the roadside. It is often seen in towns, in gardens or vacant lots.

The caterpillar is green, with dark bands spotted with yellow. Its major food plants are members of the carrot family, Apiaceae, (including fennel), and also some members of the citrus family, Rutaceae. Like all swallowtail caterpillars, if disturbed, it will suddenly sprout bright orange osmateria or "stinkhorns" from just behind its head, which give off a foul odor. The caterpillar grows to around 5 cm in length before forming a chrysalis, which is brown or green in colour and about 3 cm long.

The normal range of the Anise Swallowtail extends from British Columbia and North Dakota at its northern extreme, south to the Baja California peninsula and other parts of Mexico. It is occasionally reported from the south-east United States, but its normal range does not extend east of New Mexico, and even in the south-western states it is uncommon in the desert regions. In the southern parts of its range, the adults can be seen year-round, but in the north-west coastal regions, there are two flights, in spring and fall, while in the coldest parts of its range, there is a single flight, between April and July. In all the more northerly parts of the range, the chrysalis hibernates.

Conservation status: Secure

Issue #105

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Siamese fighting fish

The Siamese fighting fish (Betta splendens) is one of the most popular species of freshwater aquarium fish. It is a member of the gourami family (family Osphronemidae) of order Perciformes, but was formerly classified among the Anabantidae. It is native to the Mekong basin in Southeast Asia.

Siamese fighting fish, Betta splendens

The natural colouration of B. splendens is a dull green and brown, and the fins of wild specimens are relatively short; brilliantly-coloured and longer-finned varieties have, however, been developed by breeders (see In the aquarium, below.)

In the wild, the Siamese fighting fish inhabits standing or slow-moving water, including floodplains and rice paddys, at temperatures of 2430°C (7586°F). Carnivorous, it feeds on zooplankton and mosquito and other insect larvae.

B. splendens grows to an overall length of approximately 6 cm (2.5 in), and has a life span of up to two years.

The Siamese fighting fish is often called simply (if imprecisely) by its generic name, which is then treated as a common name ("betta").

Behaviour

Both instinctive and learned behaviours of B. splendens have been studied in considerable detail. Its characteristic aggressive responses are readily elicited by its own reflection in a mirror placed outside an aquarium. The capacity to turn aggressive behaviour on and off in this way, without putting the subject at the risk of physical damage inherent in staging an actual aggressive conflict, made the fish a popular subject of study by ethologists and comparative psychologists interested in studying aggression. There was a stream of research on the fish's aggressive behaviour from the 1970s, though this has reduced lately, partly because of new approaches to studying aggression arising out of sociobiology, and partly because it was realised that, even if no tissue damage was done, repeatedly eliciting aggressive responses in the fish might be a source of stress. Interesting results were obtained, however; for example was shown that the presentation of such an aggression-eliciting stimulus will act as an unconditional stimulus in classical conditioning, and as a reinforcer in operant conditioning. It is as if the fish finds the opportunity to attack another fish rewarding.

In the aquarium

Because of its beautiful colours and fin shapes, the Siamese fighting fish is popular with aquarists. In Asian countries they have long been used in a sport similar to cockfighting, where it was necessary to have aggressive short-finned fish. But today, by selective breeding, it is not uncommon to see males with an array of colors and tails. B. splendens specimens are bred for tail shapes ranging from the common veil-tail to the much-desired 180° "half-moon" tails, while still showing a stunning array of colors: marbled, Cambodian, butterfly, and chocolate are just a few examples.

To keep an individual B. splendens, a minimum tank size of 4 Litres (1 gallon) is recommended, if it will be kept in a warm room. A larger tank of 22 Litres (5 gallons) will allow use of a heater, to maintain a temperature of about 27°C (81°F). The floor of the tank should have, as a minimum, a thin (5 mm or 0.25 in) layer of gravel to increase the surface area for nitrifying bacteria to colonize. Decorations can provide hiding places, especially important when two males are housed in a divided tank, or when the betta is living in a community tank. Every decoration must be free of rough areas or sharp points which can damage the delicate fins of the bettafor this reason, silk rather than plastic plants are recommended. Live plants will improve the water quality.

In Canada and the United States, the Siamese fighting fish is sometimes sold in a vase with a plant, with the erroneous claim that the fish can feed on the roots of the plant. Betta species are carnivorous, though, and an appropriate food must be provided, such as dry "betta pellets" or live or frozen bloodworms or brine shrimp. When kept in a small container such as a vase, the fish need frequent water changes, and the container must be kept in a warm room. A larger tank with a heater will provide better living conditions. Wherever the fish is kept, water must be treated with an appropriate water conditioner before use.

Because of the aggressive nature of this species, tankmates must be chosen carefully, and two male B. splendens should not be housed in the same tank unless they are separated by a dividing wall. Females may or may not be able to coexist peacefully in the same tank depending on their temperaments. Before co-housing Siamese fighting fish with other species, their compatibility should be carefully researched, and the owner should have a back-up plan if the shared tank does not work.

Issue #106

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Giant clam

The Giant Clam (Tridacna gigas) or traditionally, paua, is the largest living bivalve mollusc. One of a number of large clam species native to the shallow coral reefs of the South Pacific and Indian oceans, they weigh an average of 440 pounds and can measure as much as 1.5 meters across.

Giant Clam, Tridacna gigas

Permanently sessile in adulthood, the creature's siphon and mantle tissues act as a habitat for the green algae on which it feeds. By day, its shell remains open unless disturbed, and in this way the symbiotic algae may receive sunlight they need to grow.

History

As is often the case with uncharacteristically large species, the giant clam has been historically misunderstood. Even reputable scientific and technical manuals once claimed that the great mollusk had caused deaths. In those days the Giant clam was also known as killer clam or man-eating clam. Versions of the U.S. Navy Diving Manual even gave detailed instructions for releasing oneself from its grasp by severing the adductor muscles used to close its shell.

Giant clams are the largest of all clam species and can grow until 1.5 meters in length.

Today, it is generally acknowledged that the giant clam is neither aggressive nor particularly dangerous; while it is certainly capable of holding one fast in its grip, the shell's closing action is actually a defensive response, and far too slow to pose any reasonable threat. No account of a human being trapped in this manner has ever been substantiated.

Conservation status

The IUCN lists the giant clams as vulnerable. There is concern among conservationists for the sustainability of practices among those who use the animal as a source of livelihood. The numbers in the wild have been greatly reduced by extensive harvesting for food and aquarium trade. Illegal trade in giant clam shells for use as decorative accoutrements abounds, and the meat, called Himejako in Japan, is prized as a delicacy.

Detail of the mantel of a Giant clam. The mantel contains light sensitive spots and if it senses danger the clam will close.

Conservation status: Vulnerable

Issue #107

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Diplodocus

Diplodocus (Latin: "double-beam") is a type of dinosaur of subgroup Sauropoda. Diplodocus lived during the Jurassic period. Scientists gave the dinosaur its name due to the way part of its skeleton was formed.

The first Diplodocus skeleton was found at Como Bluff, Wyoming in 1878 and was named Diplodocus longus ("long double-beam") by paleontologist Othniel Marsh. Other species include D. carnegiei (named after Andrew Carnegie) and D. hayi.

A statue of Diplodocus carnegiei

Diplodocus remains have been found in the Western United States of Colorado, Utah, and Wyoming. Fossils of this animal are common, except for the skull, which is often missing from otherwise complete skeletons. The skull was very small compared to the huge size of the animal, which could reach up to 27 m. Instead of the way Diplodocidae were formerly portrayed, with their necks high up in the air, it is now believed by some that the animal could only keep its head very low to the ground (for grazing), and that the very long tail served as a counterbalance for the long neck. Others think the animal could stand on its hind legs.

Species

- D. carnegiei (Hatcher, 1901)
- D. hayi (Holland, 1924)
- D. longus (Marsh, 1878; holotype)

Conservation status: Fossil

Issue #108

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Basenji

The Basenji is a breed of dog and a member of the sighthound family. The Basenji is a Congolese hunting dog that has no bark, but an odd yodelling sound. Recent DNA analysis confirms that this is one of the oldest breeds of dog. It was officially accepted into the AKC in 1943.

Basenji

Appearance

Basenjis are small, elegant-looking, short-haired dogs with erect ears, tightly curled tail, and graceful neck. Some people equate their appearance to that of a miniature deer. Their forehead is wrinkled, especially when young. Eyes are typically almond shaped, which gives the appearance of squinting with a serious look. It is not uncommon for a Basenji to stare down a person, which gives some people an unsettling feeling. The stare is not meant as an aggressive act; Basenjis feel that they are of equal stature with humans and are not intimidated by a human's interest in them.

Basenjis typically weigh around 20 to 24 pounds (9 to 11 kg) and stand about 17 inches (43 cm) tall at the withers. They are an athletic dog, and are deceptively powerful for their size. They have a graceful, confident gait like a trotting horse, and skim the ground in a "double-suspension gallop" when running flat out at their considerable top speed.

The AKC recognizes the following colorations: red/white, black/white, tricolor (red/black/white), and brindle (black stripes on a background of red)/white. There are additional variations, such as the "trindle", which is a tricolor and brindle, and several other colorations that remain in the Congo.

Tri-colored brindle (Trindle) Basenji at a hunt

Temperament

Most Basenjis have a strong dislike for contact with water, and will go to great, and sometimes amusing, lengths to avoid getting wet. On the other hand, they are extremely curious dogs, and can temporarily be completely oblivious to the pouring rain if something piques their interest. They are highly intelligent and learn quickly, but they also have a cat-like independence and "self-motivation" which can make them somewhat casual about obedience. A healthy Basenji is a mischievous and good-humored animal, and is not above testing the limits of its environment and owner just for sport. They can be aloof with strangers but form strong bonds with their owners. If not supervised or trained properly, Basenjis can become bored and destructive when left alone. Extremely quick and fast on its feet, the Basenji loves to run and chase, so much so that they are sometimes competitively raced in lure courses. There are few creatures the Basenji is likely to encounter (including its owner!) that it does not believe it can either outwit or outrun. This, combined with a virtually fearless approach to the world, make it a good idea not to allow a Basenji to run free in an unconfined area or where it may get into trouble. Basenjis can be very good with children if raised around them, but may not have much patience for them otherwise.

History

The Basenji is one of the most ancient breeds of dog. Originating on the continent of Africa, it has been venerated by humans for thousands of years. Basenjis can be seen on stele in the tombs of Egyptian pharaohs, sitting at the feet of their masters, looking just as they do today, with prick ears and tightly curled tail.

The Basenji had all but disappeared from civilization when it was rediscovered in the Congo region of Africa in 1895. There, the Basenji was highly prized by natives for its intelligence, courage, speed, and silence. They were invaluable assistants to the hunt, chasing wild game into nets for their masters. The Azande and Mangbetu tribes from the northeastern Congo region describe Basenjis, in the trade language of Lingala, as "embwa na bwasenji". Translated, this means "dogs from when we were wild" or "dogs from long ago".

Several attempts were made to bring the breed to England, but the earliest imports succumbed to disease. It was not until the 1930s that foundation stock was successfully established in England, and thence to the United States. So it is that nearly all the Basenjis in the western world are descended from these original imports. For a fascinating account of the importation of the Basenji from Africa, read The History of the Breed, a letter to the AKC in support of opening the stud book to admit new African imports.

Health

Some Basenjis are prone to Fanconi syndrome. Basenjis, along with certain other breeds of dog have been known to be carriers of a simple recessive gene which, when expressed, immediately causes Hemolytic Anemia. When lineage from a fully tested line (set of ancestors) is indefinite: a Basenji can be tested at any time before it is bred.

Alternative names:
- African Bush Dog
- African Barkless Dog
- Ango Angari
- Avuvi
- Congo Dog
- Zande Dog

Country of origin: Congo

Issue #109

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White Rhinoceros

The White Rhinoceros or Square-lipped rhinoceros (Ceratotherium simum) is one of the five species of rhinoceros that still exists and is one of the few megaherbivore species left. It is native to Northeastern and southern Africa. The rhinos tend to group in herds of one to seven animals, though they are solitary animals. On its snout it has two horns made of keratin fibers (and not bone, as in deer antlers).

A Southern White Rhinoceros, Ceratotherium simum, at the San Diego Zoo's Wild Animal Park in Escondido, California.

The White Rhino differs from the Black Rhinoceros because of the shape of its mouth it is wide, for cropping large swaths of grass; the term "White" actually comes from the Afrikaans word "weit", meaning 'wide'. A White Rhino's skin color is quite similar to that of the Black Rhino.

The White Rhinoceros also has a noticeable hump on the back of its neck which supports its large head. Each of the rhino's four feet has three toes. It is sometimes known as the Square-lipped Rhinoceros because of its protrudent lip that helps it graze on short grasses quickly in the savanna.

There are two subspecies of White Rhinos; as of 2005, South Africa has a Southern White Rhino (Ceratotherium simum ssp. simum) population of about 11,000, making them the most abundant subspecies of rhino in the world.

The Northern White Rhino (Ceratotherium simum ssp. cottoni), formerly found in several countries in East and Central Africa, are believed to exist in only three places:

- Garamba National Park in the Democratic Republic of the Congo;
- Zoo Dvur Králové in the Czech Republic, which has six rhinos; and
- San Diego Wild Animal Park, where three are located.

The rhinos have rarely reproduced in captivity; since 1995, only one female calf has been born, at Dvur Kralove.

Poaching

Like the Black Rhino, the White Rhino is under threat from habitat loss and poaching, most recently by an offshoot of the janjaweed. This increase led conservationists in January 2005 to propose airlifting White Rhinos remaining in Garamba into Kenya. Resentment of foreign interference within the Congo has prevented the airlift from happening as of March 2005.

Trivia

- The rhinos are capable of going four or five days without water.

Conservation status: Critical

Issue #110

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Great Spotted Cuckoo

The Great Spotted Cuckoo, Clamator glandarius, is a member of the cuckoo order of birds, the Cuculiformes, which also includes the roadrunners, the anis, the coucals, and the Hoatzin.

Adult and juvenile Great Spotted Cuckoo, Clamator glandarius

It is a widespead summer migrant to southeast and southwest Europe and western Asia, and winters in Africa. It is a brood parasite, which lays its eggs in the nests of corvids (especially magpies), and starlings.

This species is similar in size to Common Cuckoo, but looks larger with its broad wings and long narrow tail.

Unlike the Common Cuckoo, neither the hen nor the hatched chick of this species evict the host's eggs, but the young magpies often die because they cannot compete successfully with the cuckoo for food.

The adult is grey above with a slender body, long tail and strong legs. It has a grey cap, grey wings, a yellowish face and upper breast, and white underparts. Sexes are similar. The juveniles have blackish upperparts and cap, and chestnut primary wing feathers. This species has a magpie-like flight.

It is a bird of warm open country with trees. Its food is insects, with hairy caterpillars, which are distasteful to many birds, being a speciality.

The Great Spotted Cuckoo's call is a loud cher-cher-kri-kri and variations.

Issue #111

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Cuban Tree Frog

The Cuban Tree Frog (Osteopilus septentrionalis) is the largest species of tree frog in North America. It generally lives in central to southern Florida, though it has been seen as far north as Georgia. It is, however, not native to this region; it was somehow introduced from the Caribbean.

Cuban Tree Frog, Osteopilus septentrionalis

It is considered to be an invasive species, consuming native frogs and lizards and posing a threat to the biodiversity of the areas into which it spreads.

Issue #112

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Cochineal

Cochineal (Coccus cacti or Dactylopius coccus) is a scale insect in the order of Homoptera, indigenous to Mexico. A parasite, it lives primarily on the prickly pear cactus by feeding on moisture in its leaves.

Cochineal insects, Coccus cacti or Dactylopius coccus

Cochineal is also the name given to the crimson or carmine colored dye made from the dried bodies of the females (in the case of "cochineal") or the crushed eggs (in the case of cochineal extract).

The Insect

Cochineals are soft-bodied, flat, oval-shaped insects that cluster on plants. They secrete a waxy white substance over their bodies for protection. The feeding of the female cochineal often causes damage and sometimes kills the host cactus plant. Adult males have wings, are tiny, and cannot feed at all. They only live long enough to fertilize the eggs. Immature males can feed for a short time.

Cochineal insects on a cactus

The Dye

A deep crimson dye is extracted from the Cochineal insect female.

Dye Production

The insects are collected at approximately age of ninety days; it is a highly labor-intensive activity. The insects are killed by either immersion in hot water or by exposure to sunlight, steam, or the heat of an oven. The variety in the appearance of commercial cochineal is caused by these differing methods. It takes around 70,000 insects to make one pound of cochineal. The coloring comes from carminic acid.

History

The cochineal was used by the Aztecs. After the arrival of the Spanish conquistadors, it was introduced to Europe during the 17th century. The Mexican city of Oaxaca, Oaxaca, and its hinterland owed much of its prosperity in the 17th and 18th centuries to the cochineal trade. It has since been imported to and cultivated in other locations, such as Peru and the Canary Islands, where it became a lucrative export.

In the course of the 20th century, trade in cochineal diminished, as it was replaced by synthetic compounds. In recent years it has become commercially valuable again, because unlike many commercial synthetic red dyes, it is non-toxic and not carcinogenic (this is a point of controversy - see section below).

Usage

Traditionally cochineal was used for coloring fabrics. Now it is used as a fabric and cosmetics dye and as a natural food coloring, as well as for oil paints and watercolours. When used as a food additive, the dye may be labelled as E120 on packaging labels.

Wool dyed with cochineal

The water soluble form is used in alcoholic drinks with calcium carmine, the insoluble form, being used in a wider variety of products. Together with ammonium carmine they can be found in alcoholic drinks, bakery products and toppings, biscuits, desserts, drinks, icings, pie fillings, variety of cheddar cheese, sauces and sweets. It is also thought to give Campari and other Italian aperitifs their color.

Controversy

An unknown percentage of people have been found to have allergies to carmine, ranging from mild cases of hives, to anaphylactic shock. Cochineal is one of the colors that the Hyperactive Children's Support Group recommends be eliminated from the diet of hyperactive children.

Natural carmine dye used in foods can render them rather unattractive to vegetarian consumers, since insects are used in dye production.

Foodstuffs containing carmine are considered haraam (forbidden) by Muslims.

Issue #113

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Walking catfish

The walking catfish (Clarias batrachus), also known as the magur or pla duk dam, is a species of airbreathing catfish with the ability to "walk" out of the water and across land.

Walking catfish, Clarias batrachus

It is a native of Southeastern Asia including eastern India, Sri Lanka, Bangladesh, Burma, Indonesia, Singapore, and Borneo. It was probably introduced into the Philippines.

In the United States it is a non-indigenous invasive species, which is now established in Florida and reported from California, Connecticut, Georgia, Massachusetts, and Nevada.

The walking catfish was imported to Florida, reportedly from Thailand, in the early 1960s for the aquarium trade. The first introductions apparently occurred in the mid-1960s when adult fish imported as brood stock escaped, either from a fish farm in northeastern Broward County or from a truck transporting brood fish between Dade and Broward counties. Additional introductions in Florida, supposedly purposeful releases, were made by fish farmers in the Tampa Bay area, Hillsborough County in late 1967 or early 1968, after the state banned the importation and possession of walking catfish. Aquarium releases likely are responsible for introductions in other states. Dill and Cordone (1997) reported that this species has been sold by tropical fish dealers in California for some time.

In Florida, walking catfish are known to have invaded aquaculture farms, entering ponds where these predators prey on fish stocks. In response, fish farmers have had to erect protective fences to protect ponds.

Issue #114

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Northern Shrimp

The Northern shrimp, Pandalus borealis (also called Pandalus eous), is a species of shrimp found in cold parts of the Atlantic and Pacific Oceans. Many different English names are used, with little consensus (deep-water shrimp, cold-water shrimp, northern shrimp, Alaskan pink shrimp, pink shrimp, and northern red shrimp). Often the word shrimp is replaced by prawn, albeit incorrectly.

Northern shrimp, Pandalus borealis

P. borealis is an important food resource, and is widely fished. Its distribution in the Atlantic ranges from New England, Canada's eastern seaboard, southern and eastern Greenland, Iceland, Svalbard, Norway and the North Sea as far south as the English Channel. In the Pacific, it is found from Japan, through the Sea of Okhotsk, across the Bering Strait, and as far south in North America as Washington state. They live at depths of between 10 and 500 m, usually on soft muddy bottoms, in waters between 2 °C and 14 °C. In their 3-4 year lifespan, individuals can reach a length of 120 mm, with a carapace 35 mm long.

Shrimp alkaline phosphatase (SAP), an enzyme used in molecular biology, is obtained from Pandalus borealis.

Issue #115

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Pyrenean Ibex

The Pyrenean Ibex, Capra pyrenaica, once ranged from Sierra de los Nieves in the province of Malaga into the French Pyrenees. A few hundred years ago they were numerous, but by 1900 their numbers were reduced to less than one hundred. Moreover, since 1900, their numbers have never risen above 40.

Pyrenean Ibex, Capra pyrenaica

The last Pyrenean Ibex was found dead on January 6, 2000. The reason the Ibex became extinct is a mystery. Some hypotheses include the inability to compete with other species for food, infections and diseases, and poaching.

The Pyrenean Ibex was one of four subspecies of Ibex. This is the best known species with smoother and more spreading horns.

Range and Population

Formerly found in the Spanish Pyrenees. However, more recently the population was restricted to Ordesa National Park in Spain.

Habitat

Capra pyrenaica preferred rocky, mountainous habitat. Its diet consisted of grass, herbs and lichens.

Taxonomy

The Pyrenean Ibex is in the Order Artiodactyla (even-toed ungulates). These animals are paraxonic which means that the plane of symmetry of each foot passes between the third and fourth digits. The third and fourth digits are quite large and bear most of the weight.

The Pyrenean Ibex is of Family Bovidae. All bovids have horns. Their skulls lack sagittal crests. They have hypsodont teeth.

Conservation status: Extinct (2000)

Issue #116

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Japanese Bobtail

The Japanese Bobtail is a breed of cat with an unusual 'bobbed' tail more closely resembling the tail of a rabbit than that of an ordinary feline. The short tail is caused by the expression of a recessive gene. Thus, so long as both parents are bobtails, all kittens born to a litter will have bobtails as well.

A Calico (called "Mi-ke") Japanese Bobtail cat

The bobtail is a small oriental cat native to Japan and Southeast Asia. The breed has been known in Japan for centuries, and there are many legends and myths, as well as pieces of ancient art, featuring it. The Maneki Neko, or 'beckoning cat' is a bobtail.

Japanese bobtails may have almost any colour, but calico (called "Mi-ke", meaning "three-fur") or bi-colours are especially favoured by the Japanese.

Issue #117

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Red Wolf

The Red Wolf (Canis rufus) is the rarest and most endangered of all wolves. It is said to have no natural predators. It is thought that its original distribution included much of eastern North America, where Red Wolves were found from Pennsylvania in the east to Texas in the south. In the last century, however, persecution, habitat destruction, and hybridization with Coyotes has brought the Red Wolf to the brink of extinction. Only about 270 remain; about 100 reintroduced into the wild in North Carolina and 170 in captivity. Historical habitats included forests, swamps and coastal prairies.

Red Wolf, Canis rufus

Traditionally, three subspecies of Red Wolf have been recognised, two of which are extinct. Canis rufus floridanus has been extinct since 1930; Canis rufus rufus was declared extinct by 1970; and Canis rufus gregoryi, the surviving subspecies, became extinct in the wild by 1980.

Anatomy

The Red Wolf is a medium-sized canid, smaller and more slender than the Grey Wolf but larger than the coyote. Adult males weigh between 25-35 kilograms (60-80 lbs) while females are generally two-thirds this range. Their coats may take a variety of colours: black, brown and grey through cinnamon and yellow. The reddish coats for which they are named was typical of some Texan populations. In the wild average life spans are estimated as low as four years; in captivity this rises as high as fourteen years.

Habits and Social Structure

Red wolves are shy and wary creatures. They prefer to hunt alone or in small family groups; pack sizes are smaller than those of their grey cousins, consisting often of one adult pair and their offspring.

As in other canids pair-bonding is strong and red wolves mate for life. They mate yearly and two or three pups are usually born in the Spring. Both parents help raise the offspring who are mature enough to leave behind parental support at six months of age.

Their diet consists of any available small animal, including rabbits, raccoons and rodents. They occasionally bring down deer and supplement their diet with insects and berries.

Taxonomy

The taxonomic status of the Red Wolf has long been controversial: the traditional view is that it is indeed a distinct species. An alternative view is that the Red Wolf is simply a recent hybrid between the Grey Wolf and the Coyote. In this view, Red Wolves arose when habitat loss and human disruption caused remnant Grey Wolf and Coyote populations to interbreed.

Extensive studies have thrown much light but little clarity on the question. On the whole, morphological, behavioural, and genetic evidence supports the view that there has been a distinct Red Wolf population for over half a million years, but much confusion and not a little controversy remains. There seems little doubt that there has been considerable hybridisation between Red Wolves, Grey Wolves, and Coyotes, and that in recent years the Red Wolf has declined and been replaced over most of its range by Coyotes and Coyote-Red Wolf hybrids.

In 1999, Brad White of McMaster University and Paul Wilson of Trent University found evidence suggesting that the wolves of south-eastern Canada (previously assumed to be Grey Wolves) were in fact Red Wolves, a view which has since found support in both fossil and morphological evidence. The Eastern Canadian Wolf, as this population has been named, ranges from Minnesota to Quebec.

One recent theory suggests that Red Wolves, Grey Wolves and Coyotes are all descended from a common ancestor population in North America between one and two million years ago. According to this theory, the ancestors of the Grey Wolf migrated to Europe and Asia at that time, becoming the Grey Wolf as we know it today, and then returned to the Americas about 300,000 years ago. At around the same time (300,000 years ago) the Coyote and Red Wolf populations diverged and began to differentiate. The modern Eastern Canadian Wolf population, in this view, is a mixture of different blood lines, including pure Grey Wolves, pure Red Wolves, and hybrids between Red Wolves and Coyotes, and Red Wolves and Grey Wolves. Grey Wolves and Coyotes do not hybridise directly.

The upshot of the taxonomic debate is not simply a matter of accurate classification: although the actual patterns of evolution are complex and subtle, human classification schemes usually rely on relatively simple, hard-edged divisions, such as the concept of species, which is ill-adapted to describing the wolves of North America. It remains a crucial concept, however, as many environmental policy decisions revolve around the species concept. In law, a distinct "species" is much better protected than a "mere subspecies".

Conservation status: Critical

Issue #118

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California Quail

The California Quail, Callipepla californica, is a small ground-dwelling bird in the New World quail family.

These birds have a curving crest that droops forward - black in males and brown for females; the flanks are brown with white streaks. Males have a dark brown cap and a black face with a brown back, a grey-blue chest and a light brown belly. Females and immature birds are mainly grey-brown with a light-coloured belly.

California Quail, Callipepla californica

Their breeding habitat is shrubby areas and open woodlands in western North America. The nest is a shallow scrape lined with vegetation located on the ground under a shrub or other cover. The female usually lays around 12 eggs. Once they are hatched, both parents look after the young.

They are permanent residents.

These birds forage on the ground, often scratching at the soil. They can sometimes be seen feeding at the sides of roads. Their diet consists mainly of seeds and leaves, but they also eat some berries and insects. If startled, these birds explode into short fast flight. Given a choice, they will normally make their escape on foot.

They often gather in small flocks known as "coveys". Although this bird coexists well at the edges of urban areas, it is declining in some areas as human populations increase. They were originally found mainly in the southwestern United States but they have been introduced into other areas including British Columbia, Hawaii, Chile and New Zealand.

This is the state bird of California.

Issue #119

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Scarlet Kingsnake

The Scarlet Kingsnake (Lampropeltis triangulum elapsoides) is a type of king snake that is found in the Eastern portion of the United States, particularly Florida. It is a subspecies of the Milk Snake, Lampropeltis triangulum. It is significantly smaller that some of the other king snakes, usually well under 20 inches long.

Scarlet Kingsnake, Lampropeltis triangulum elapsoides, on a US postage stamp

The snake has a pattern of black, red, and yellow bands that mimics the venomous Coral Snake. The key to differentiate between the two is found in the popular phrase "red on yellow, kill a fellow; red on black venom lack". Another version of the rhyme is "If red touches yellow, you're a dead fellow; if red touches black, you're alright, Jack", or "Red and black is a friend of Jack". In other words, if the red bands don't touch the yellow bands, you are normally dealing with a Scarlet King Snake.

Juvenile specimens of this snake often have rings that look more "off white" than yellow.

Issue #120

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Atlas moth

The Atlas moth (Attacus atlas) is a large saturniid moth found in the tropical and subtropical forests of Southeast Asia, common across the Malay archipelago to Indonesia. In India, Atlas moths are cultivated for their silk in a non-commercial capacity; unlike that produced by the related Silkworm moth (Bombyx mori), Atlas moth silk is secreted as broken strands. This brown, wool-like silk is thought to have greater durability and is known as "fagara." Atlas moth cocoons have been employed as purses in Taiwan.

A female Atlas moth, Attacus atlas

Atlas moths are considered to be the largest moths in the world in terms of total wing surface area (upwards of c. 400 square cm or 65 square inches). Their wingspans are also amongst the largest, from 25-30 cm (10-12 inches). Females are appreciably larger and heavier. (The largest lepidopteran in terms of wingspan is thought to be the owlet moth Thysania agrippina.) Atlas moths are said to be named after either the Titan of Greek mythology, or their map-like wing patterns.

Atlas moths are predominantly tawny to maroon in colour with roughly triangular, diaphanous "eyes" on both forewing and hindwing, bordered in black. The purpose of these dramatic, gossamer portals is not clear, but they are thought to play a role in predator avoidance. Their bodies are hairy and disproportionately small compared to their wings. Patterns and colouration vary among the many described subspecies. Male Atlas moths are distinguished from females by their smaller size, more tapered wings, and larger, bushier antennae. Neither sex possess fully-formed mouthparts and therefore do not feed; they survive entirely on larval fat reserves throughout their 1-2 week adult life.

Forewing of a female Atlas moth

Females are sexually passive, releasing powerful pheromones which males detect and home in on with the help of chemoreceptors located on their aggrandized, feathery antennae. Males may thus be wooed from several kilometres downwind. Atlas moths are unsteady fliers and the female barely strays from the location of her discarded chrysalis: she seeks a perch where the air currents will best carry her pheromones.

Following a curt romance, the female lays a number of spherical eggs 2.5 mm in diameter on the undersides of leaves. Dusty-green caterpillars hatch after about two weeks and begin to tirelessly feed on the foliage of certain citrus and other evergreen trees. The caterpillars are adorned with fleshy spines along their backs which are covered in a waxy white substance. After reaching a length of about 115 mm (4.5 inches), the caterpillars pupate within papery chrysalides redolent of desiccated leaves. The adult moths emerge after about four weeks.

Interestingly, Atlas moths are also capable of parthenogenesis: any unfertilized eggs laid by a female will develop into males.

The Atlas moth was first discovered in the Sanjay Gandhi National Park, Mumbai, India.

Issue #121

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Kissing gourami

Kissing gouramis, also known as kissers (Helostoma temminckii), are large tropical freshwater fish comprising the monotypic gourami family Helostomatidae (from the Greek elos [stud, nail], stoma [mouth]). Highly commercial food fish which are farmed in their native Southeast Asia, kissing gouramis are also popular with aquarists for the fish's peculiar "kissing" behaviour.

Pink Kissing gourami, Helostoma temminckii, rasping algae from gravel

Physical description

Typical of gouramis, the body is deep and strongly compressed laterally. The long-based dorsal (1618 spinous rays, 1316 soft) and anal fins (1315 spinous rays, 1719 soft) mirror each other in length and frame the body; the posterior most soft rays of each are slightly elongated to create a trailing margin. The foremost rays of the jugular pelvic fins are also slightly elongated. The pectoral fins are large, rounded, and low-slung. The caudal fin is rounded to concave. The lateral line is divided in two, with the posterior portion starting below the end of the other; there are a total of 4348 scales running the line's length.

The most distinctive feature of the kissing gourami is its mouth. Other than being terminal rather than superior (as in other gourami families), the kissing gourami's mouth is highly protrusible; as its family name suggests, the lips are lined with horny teeth. However, teeth are absent from the premaxilla, dentaries, palatine, and pharynx. The gill rakers are also well-developed and numerous. The eye-visible scales of the body are ctenoid, whereas the scales of the top of the head are cycloid. Kissing gouramis reach a maximum size of 30 cm (12 inches) total length. There is no outward sexual dimorphism, but females are characteritically fatter.

This head-on view provides a close look at the kissing gourami's distinctive mouth structure.

There are two colour morphs encountered: the natural greens, which have lengthwise lateral stripes and opaque, dark brown fins; and the pseudo-albino pinks, which have a rose to orangy pink body and silvery scales, with transparent pinkish fins. There is also a "dwarf" or "balloon pink" variety, which is a mutated strain of the pink gouramis that are offered to hobbyists. The "balloons" are named so for their smaller and rounder bodies.

In the wild

Shallow, slow-moving, and thickly vegetated backwaters are the kissing gourami's natural habitat. They are midwater omnivores that feed primarily on benthic algae and aquatic plants, with insects taken from the surface and zooplankton and phytoplankton filtered through their many gill rakers supplementing their diet. The fish use their toothed lips to rasp algae from stones and other surfaces. This rasping action, which (to humans) looks superficially like kissing, is also used by males to challenge the dominancy of conspecifics.

Spawning occurs from May to October in Thailand. Kissing gouramis are open-water egg scatterers; spawning is initiated by the female and takes place under cover of floating vegetation. The eggs, which the adults do not guard, are spherical, smooth, and buoyant. Initial development is rapid: the eggs hatch after one day, and the fry are free-swimming two days thereafter. The Kissing gourami is the only member of the suborder Anabantoidei not to build a nest or otherwise care for its young.

In the aquarium

Kissing gouramis need a roomy tank in order to thrive; small juveniles will quickly outgrow a 70 cm (27 inch) tank. Kissing gouramis are tolerant toward conspecifics and heterospecifics of similar size, although male kissers will occasionally challenge each other; however, the "kissing" is never fatal. To prevent digging and to present enough surface area for algae growth, the substrate should consist of large-diameter gravel and stones. The aquarium's back glass should not be cleaned during regular maintenance, as the gouramis will feed on the algae grown there. Most plants will not survive the fish's grazing, so inedible plants such as Java fern, Java moss, or plastic plants are recommended.

The fish will accept vegetables such as cooked lettuce and any kind of live food. Water hardness should be between 530°dGH and pH between 6.88.5; the temperature should be between 2228°C (7282°F). When breeding kissing gouramis, soft water is preferred. As the fish do not build a nest, lettuce leaves placed on the water surface serve as a spawning medium. The lettuce will eventually host bacteria and infusoria which the fry will feed upon.

Issue #122

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House dust mite

The house dust mite (Dermatophagoides pteronyssinus in Europe and Dermatophagoides farinae in North America), sometimes abbreviated by allergists to HDM, is a cosmopolitan guest in human habitation, gaining scientific prominence only in the 1600s after the importance of sanitation was recognized. They are considered to be one of the most common causes of asthma worldwide.

House Dust Mite, Dermatophagoides pteronyssinus

Description

Both male and female adult house dust mites are globular in shape, creamy white and have a striated cuticle. The female measures approximately 420 micrometres in length and 320 micrometres in width. The male is approximately 420 micrometres long and 245 micrometres wide. A member of the phylum Arthropoda, house dust mites have eight legs.

The average life cycle for a male house dust mite is approximately 19-30 days while a mated female house dust mite can live for up to two months, laying eggs for the last 30 days of her life.

Habitat

The house dust mite is more common in Europe than North America. The mite thrives in the modern environment of fully-carpeted, double-glazed, draft-proof homes, and is comfortable at 25 degrees Celsius and 75% relative humidity. The mites are particularly common in carpets and bedding.

The mite generally lives on shed human skin cells, which are pre-digested by the fungus Aspergillus repens. An average person sheds about 1.5 grams of skin a day (approximately 3-4.5 kg per year), which is enough to feed roughly a million dust mites. Further, dust mites in bedding derive moisture from human breathing, perspiration, and saliva.

Asthma

The house dust mite is one of the most significant allergens, implicated in allergic asthma, rhinitis, conjunctivitis and dermatitis. The protein responsible for the allergic reaction is DerP1, a protease digestive enzyme found in mite feces.

Measures to control house dust mites:

- Do not use a vacuum cleaner (bags and bagless are dust blowing tools)
- Regular damp dusting of surfaces
- Replacement of carpets with vinyl flooring
- Covering of mattresses and pillows with impervious materials
- Daytime internment of children's plush toys in a freezer
- Use of chemicals to kill mites (acaricides)
- Use of fungicides to kill Aspergillus
- Use an FDA approved air filtration & cleaning system (especially with high-efficiency particulate air (HEPA+ filtration)
- Reduce ambient humidty below 70% to inhibit growth of Aspergillus

Though these methods can help to reduce the level of house dust mites, attempts to eradicate homes completely have yet to be successful. Immunotherapy, in the form of injections of the allergen into patients, has been successful for some in much the same way that "allergy shots" have been helpful for sufferers of hayfever.

Conservation status: Secure

Issue #123

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Iguanodon

Iguanodon was the first dinosaur recognized, the second dinosaur formally named and described, and with Megalosaurus and Hylaeosaurus, one of the three originally used to define the new classification, Dinosauria.

Reconstruction of the Iguanadon from BBC's Walking With Dinosaurs

Description

The Iguanodon is an ornithopod dinosaur, roughly halfway between the early "hypsilophodontids" and their ultimate culmination in the duck-billed dinosaurs. They lived between 120 to 140 million years ago, in the Barremian to Valanginian ages of the early Cretaceous period, though one unknown species is from the late Jurassic.

The various Iguanodon species are bulky herbivores, ranging from 6 to 11 metres (20 to 36 feet) in length, and averaging about 5 tonnes (5.5 tons) in weight.

Discovery and classification

Gideon Mantell's wife, Mary Ann, discovered the first tooth of an Iguanodon in the Tilgate Forest in England, in 1822. The tooth resembled that of an iguana, but was twenty times larger, so he named it Iguanodon, or "iguana-toothed", from iguana and the Greek word odontos ("tooth"). Based on isometric scaling, he estimated it might be up to 60 feet (18 metres) long.

A better specimen was discovered in a quarry in Maidstone, which Mantell was able to identify as an Iguanodon based on the tooth. The Maidstone slab allowed the first skeletal reconstructions and artistic renderings of the Iguanodon. The most famous mistake was the placement of a "horn", also discovered by Mantell's wife, on the nose of the dinosaur. The discovery of much better specimens of I. bernissartensis in 1878 revealed that the horn was actually a modified thumb, perhaps used for defense.

Still encased in rock, the Maidstone slab is currently displayed at the Natural History Museum, in London. The borough of Maidstone commemorated this find by adding an Iguanodon to their coat of arms in 1949.

Borough of Maidstone coat of arms (note the Iguanodon on the left)

Iguanodon anglicus was the original type species, but the holotype was based on a single tooth, and only partial remains of the species have been recovered since. In March of 2000, the ICZN changed the type species to I. bernissartensis, which is known from dozens of skeletons, some of which are very complete.

Remains of the best-known Iguanodon species have been found predominantly in Belgium, England, Germany, Spain and France. Remains of similar animals have been found in Tunisia and Mongolia, and distinct species have been found in Utah and South Dakota.

The largest find of Iguanodon remains occurred in 1878 in a coal mine at Bernissart in Belgium. With the encouragement of Alphonse Briart, supervisor of mines at nearby Morlanwelz, Louis Dollo oversaw excavation and reconstructed the skeletons. Some were publicly displayed from 1882; the completed restoration makes an impressive display in the Royal Belgian Institute of Natural Sciences in Brussels.

Species

I. anglicus
I. atherfieldensis
I. bernissartensis (type)
I. dawsoni
I. fittoni
I. hoggi
I. lakotaensis

Conservation status: Fossil

Issue #124

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