Editor Letter
Editorial
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I think breakfast is the one meal when you don’t have to eat animal, maybe. Elderton Stocks | Editor
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henever I visit one of our national parks and reserves, Iam amazed to hear so many foreign languages. People travel from arround the world to enjoy what we take for granted. Further proof of the huge interest other nations and cultures take in our natural heritage are the thousand of overseas clicks each month on the wildmagz.com website. Which prompts me to wonder: how many South Africans have visited a Wild Magazine property? Have You? The sheer variety of our parks includes unequalled scenery and wildlife, from desertscapes to stromy coasts and glorious bushveld. So too the range of accomodation on offer. There is truly something for everyone, from camping in your own tent or caravan to luxury safari tents, chalets, bungalows, lodges and guesthouses that become your own during the length of your stay. To whet your appetite for our magnificent destinations, March 2013
we’ve compiled a roundup that will have you reaching for your road atlas. The highlight are undoubtedly Swaziland’s Big Game Parks, which are full of surprises. What’s more, they are such convenient destinations for Wild Animal Magazine members in the nothern parts of the country. For those in the south, our special treat is Agulhas National Park, which now has loads of great place to stay. Go take a look, the park literally teems with life. Have you compiled a bucked list for 2014? How are you doing so far? Now that we’ve reached the midyear mark, I have become jittery about my own res olutions and will soon be off in search of the one sighting that has eluded me so far; wild dogs. This year I’ve visited De Hoop Nature Reserve, Camdeboo National Park and Mountain Zebra National Park. Each of these provided an entirely different experience and they all exceeded my wildest expectations. Let’s hit the road! Animal Magazine WILD
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Content
Content MARCH 2013
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New Mammalian Discoveries
4 Mamalia 6
The Mammalian Mother
11 Amphibians 14
Red - Eyed Tree Frog
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Poison Frogs Dress in Hometown Colors
24 Fish 22
Red - Eyed Tree Frog
28 Reptiles 27
Red - Eyed Tree Frog
18 Aves 20
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Birds In Arctic
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March 2013
Content
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Birds In Antarctic
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The Puffer Fish
March 2013
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Saving the World’s Most Endangered Sea Turtle Animal Magazine WILD
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Mammals
MAMMALS
WILD ANIMAL MAGAZINE 4
WILD Animal Magazine
March 2013
Mammals
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ammals (Class Mammalia) belong to a group of vertebrates that includes approximately 5,400 extant species. Mammals display a remarkable array of adaptations that enable them to inhabit a wide range of habitats. Mammals range in size from the minute Bumblebee Bat which measures a mere three centimeters in length, to the magnificent blue whale, which can measure 33 metres head to tail—at such immense dimension, it is undoubtedly the largest animal alive today.
CUSCUS The cuscus is a large marsupial native to the Northern forest of Australia and the large, tropical island of Papua New Guinea. The cuscus is a subspecies of possum with the cuscus being the largest of the world’s possum species. The cuscus is known to range in size from just 15cm to more than 60cm in length, although the average sized cuscus tends to be around 45cm (18inches). The cuscus has small ears and large eyes which aid the cuscus through it’s nocturnal lifestyle.
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Mammals
Orangutan The Orang-utan is one of the largest primates in the world and is the only member of the Great Ape family that is found outside of Africa. There are two species of Orangutan found in the steamy jungles on the islands Borneo and Sumatra which are the Bornean Orang-utan and the Sumatran Orang-utan. The Bornean Orang-utan is more numerous and widespread than it’s cousins on Sumatra with three distinct subspecies of Bornean Orangutan found in differing geographic regions on the island.
The Mammalian Mother
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he main thing that sets mammals apart from all the other animal groups, is the fact that the females of each mammalian species have mammary glands. These organs are found only amongst mammals and they produce milk with which the female can feed her young, giving them the best possible start in life. The young suckle on the teats/ nipples of their mother in order to consume this nutritious feast. However, these milk-producing glands can often mean that the offspring of mammals are much more vulnerable at birth than those of other animal groups, as they rely more heavily on the care and protection of their mother. Some baby mammals are in fact 6
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so underdeveloped at birth, that they are born hairless and blind and are often dependent on their parents (mainly mum) for a significant amount of time. A Young Hedgehog New-born African Elephant calves weigh around 3% of their total adult weight and stand at about 90cm tall. They are known to drink nearly 11.5 litres of milk every day but unlike many other species, it is not just their mother that feeds
them, as African Elephant calves are also cared for by other females in the herd. They are generally dependent on their mother for up to 5 years, although some may not be weaned until they are nearly 10 years old. Baby Hedgehogs on the other hand, are not dependent on their mother for quite so long, but are born without their spikes and they cannot see. By the end of their second week, the Hedgehog pups have spikes and their fur has started to grow, with their eyes also having opened. They are weaned at between 3 and 4 weeks of age, and begin to accompany their mother on foraging trips before they leave the nest and have to fend for themselves. Young Koala In Tree March 2013
Mammals
Australian Bats With over 90 species, Australia’s bat fauna is diverse, covering many different habitats. Find out more about some Australian bat species and where they are found.
Koala babies however, are more dependent on their mother as they are born at about an inch in length and weigh less than a gram. As with all marsupials, the female Koala has a pouch on her underside, which the joey crawls into after birth. They are then able to attach themselves to one of two teats inside their mother’s pouch, where they remain suckling milk for up to 6 months before they March 2013
start to venture out. Cheetah same amount as a mouse and cubs are born blind, hairless and are hairless and blind, generally unable to really move at all. The not opening their eyes until they mother suckles and protects are nearly two months old. They between 4 and 6 young for up tend to remain under the watchful to 18 months when she guidance of their mother eventually abandons until they are three them to fend for years old and can themselves. venture into the “Which is often a Sadly, it thought bamboo forests that up 90% of on their own. real struggle for many Cheetah cubs mammalian mothers around 10 Month Old in some parts Panda the world.” of Africa don’t As you can survive their first see, despite three months as all belonging to they are so helpless the same animal and vulnerable. Cheetah group, species all appear cubs weigh less than 300 to develop and then care for grammes at birth and measure their young differently, which is about 30cm long. often a real struggle for many A Cheetah Cub Over in the Far mammalian mothers around East, generally two Giant Panda the world. Humans in the west cubs are born to their mother however, have by far the longest but it is very rare that more than dependence on their mothers, one will survive. At birth Giant leaving home at an average age of Panda cubs weigh about the between 16 and 18 years old.
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Mammals
New Mammalian Discoveries
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hen 2010 was first made the Year of Biodiversity, who would have known that such a wealth of knowledge into the lives of other animals would come to light. Thousands of new species were discovered last year but it is quite rare today that new mammalian species are being documented, particularly in areas where their native habitats are severely under threat. So it was a real surprise when during this year’s Myanmar Primate Conservation Program, a new species of snub-nosed monkey was reported by local hunters who had never seen the animal before. After further investigation, researchers found that this new species of snubnosed monkey (Rhinopithecus strykeri) was unique from others not only by it’s upturned nostrils, but also the fact that they are usually only found in China and Vietnam and have never been documented in Myanmar before.
two of Asia’s largest rivers, the Salween and the Mekong. These black monkeys differ from their relatives as they have long tails, white ear tufts, chin beards and wide upturned nostrils that are said to cause them to sneeze when it rains. All snubnosed monkeys are Critically Endangered species mainly due to hunting and habitat loss. Meanwhile, on the equally isolated island of Madagascar, researchers have been visiting it’s biggest lake since 2004 studying what could be the world’s rarest carnivore. There are thought to only be two individuals inhabiting the demising wetlands, which this year, has been formally identified as a new species known as the Durrell’s Vontsira, a mongoose-like mammal related to the other vontsira species on the island and named in honour of conservationist Gerald Durrell.
A European Mouse-Eared Bat And finally, in the moist forests of north-western Ecuador, what is thought to be one of the smallest species of mouse-eared bats in South America has been formally identified as a new species (Myotis diminutus) after the first specimen was collected in 1979. After 31 years, it has finally been given it’s own name but is thought to be seriously under threat from habitat degradation. It is one of five mammalian species to be found in the area in recent years.
Kachin State, North Myanmar The small population of around 300 individuals, is thought to have been isolated from other snub-nosed monkey species by
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Mammals
March 2013
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Amphibians
AMPHIBIANS
Animals that are born in the water and then live on the land are called amphibians. They lay eggs that are soft and have no shells. They dry up easily so they must be layed by the water or in wet places. Most baby amphibians are born in the water. They look like baby fish and breathe with gills as a fish does.
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Amphibians
Poison Frogs Dress in Hometown Colors
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oison dart frogs are a group of frogs that are native to the tropical jungles of Central and South America. Poison dart frogs excrete toxins through their skins, and the brightly coloured bodies of poison dart frogs warn potential predators not to eat them. Poison dart frogs vary in size, colour and the levels of toxin
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that they produce depending on the species of poison dart frog and the area in which it lives. There are more than 175 different species of poison dart frog known to be inhabiting the jungles across Central and South America. Poison dart frogs are often known as dart frogs or poison arrow frogs due to the fact that
the tribespeople living close to the poison dart frogs, would use their poison in order to tip the ends of their arrows and blow-darts. Poison dart frogs live on the ground or in the foliage just above it. Poison dart frogs are found in moist and humid forests that are free from high March 2013
Amphibians
levels of pollution. Today, many species of poison dart frogs are considered to be critically endangered in the wild, mainly due to pollution and habitat loss. Poison dart frogs are carnivorous animals that survive on a diet purely made up of meat. Poison dart frogs shoot out their long, sticky tongues to catch flies, ants, March 2013
insects, spiders and termites. Due to the high toxin levels produced by the poison dart frog, it has very few predators in the wild. Many animals will become extremely sick from just licking a poison dart frog, so they won’t approach them. There is only one species of snake that is known to be immune to the poison of the poison dart frog. Many species of poison dart
frog, make devoted parents as they carry their newborn hatchings from ground-level where they were laid to the safety of the canopy above. The eggs stick to mucus on the back of the mother poison dart frog, while she carries it a water-pool in a flower high in the trees. The female poison dart frog does this with all of her babies, and lays an unfertilised egg in the water for her young to eat. Animal Magazine WILD
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Amphibians
Red-Eyed Tree Frog
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any scientists believe the red-eyed tree frog developed its vivid scarlet peepers to shock predators into at least briefly questioning their meal choice. These iconic rain-forest amphibians sleep by day stuck to leaf-bottoms with their eyes closed and body markings covered. When disturbed, they flash their bulging red eyes and reveal their huge, webbed orange feet and bright blue-andyellow flanks. This technique, called startle coloration, may
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give a bird or snake pause, offering a precious instant for the frog to spring to safety. Their neon-green bodies may play a similar role in thwarting predators. Many of the animals that eat red-eyed tree frogs are nocturnal hunters that use keen eyesight to find prey. The shocking colors of this frog may over-stimulate a predator’s eyes, creating a confusing ghost image that remains behind as the frog jumps away. Red-eyed tree frogs, despite their conspicuous coloration,
are not venomous. They are found in tropical lowlands from southern Mexico, throughout Central America, and in northern South America. Nocturnal carnivores, they hide in the rain forest canopy and ambush crickets, flies, and moths with their long, sticky tongues. Red-eyed tree frogs are not endangered. But their habitat is shrinking at an alarming rate, and their highly recognizable image is often used to promote the cause of saving the world’s rain forests.
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Special Edition
List of All Whale Types Whales are the biggest mammals and are under the classification of Cetaceans. They are further divided into two groups based on whether they have a set of teeth (Odontoceti) or no teeth (Mysticeti).
Blue Whales Blue whale is the type of whale more familiar to a lot of people since it often represents the largest mammal in the whole world. It can grow as long as 108 feet and can reach a weight of more than 172 metric tons. A blue whale has elongated and lean body. The dorsal area’s color varies in shades of bluish grey and lighter shade underside the body.
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Orca Whales An orca whale is more known as the killer whale. It is a very violent type of whale but does not establish threat to humans. An orca whale that reaches adulthood can grow as long as 105 feet and can reach a weight of almost 200 metric tons. An orca whale has a black back and white sides and chest. Its eyes have white patches behind and above. A baby whale has a yellowish color in its skin. This fades away later on and becomes white as the whale matures. This type of whale is the largest of the dolphin family.
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Humpback Whales Humpback whale or the Baleen whale that reaches adulthood can grow as long as 50 feet and can reach a weight of 36,000 kilograms. Its significant features are the unique body shape, elongated pectoral fins, and a knobby head. A humpback whale loves to show off its acrobatic talents such as slapping and rupturing the water.
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Gray Whale A gray whale is often called the Devil Fish because it fights really hard when hunted. An adult whale can grow as long as 52 feet and can reach a weight of 36 tons. Its significant feature is the dark slated grays color of the skin and gray and white patches spread all over the whale’s body.
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Special Edition
Sperm whale A sperm whale has the largest tooth on all mammals on earth. It is called a sperm whale because of the white and waxy substance excreted in its head. It was mistaken that the substance was the whale’s sperm. Although, everyone knows that it’s not sperms, the name remains. 5An adult whale can grow as long as 67 feet and can reach a weight of up to 57000 kilograms.
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Beluga Whale A beluga whale or the white whale that reaches adulthood can grow as long as 15 feet and can reach a weight of up to 1600 kilograms for male and up to 1200 for females. A newly born beluga whale has a brown or gray colored skin. This color fades and becomes whitish grey or white as the whale matures. This type of whale has a fatty and oily bump on the forehead’s center.
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Fin Whale A fin whale or the finback whale that reaches adulthood can grow as long as 88 feet and can reach a weight of 70000 kilograms. Thus, letting it grab the second spot as the largest whale in the world. Its features are the brownish grey color of its top skin and a whitish color underneath, a pointed snout, a pair of blowholes, and a broad and flat rostrum. Fin whales are already endangered species.
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Aves
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March 2013
AVES Aves
The vertebrate class Aves includes the birds, an extremely distinctive and successful clade, with an estimated 9000 species worldwide, including the snowy owl pictured here. Although descended from the dinosaurs, birds have evolved remarkable specializations for flight: a unique “one-way� breathing system, light yet strong hollow bones, a skeleton in which many bones are fused or lost, powerful flight muscles, and -- most importantly -feathers.
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Aves
Birds In Arctic
Snowy Owl
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he ghostlike snowy owl has unmistakable white plumage that echoes its Arctic origins.
These large owls breed on the Arctic tundra, where females lay a clutch of 3 to 11 eggs. Clutch size depends upon the availability of food, and in particularly lean times a usually monogamous pair of owls may not breed at all. Parents are territorial and will defend their nests against all comers—even wolves. Young owls, especially males, get whiter as they get older. Females are darker than males, with dusky spotting, and never become totally white. Some elderly males do become completely white, though many retain small flecks of dusky plumage.
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talons. A snowy owl’s preferred meal is lemmings—many lemmings. An adult may eat more than 1,600 lemmings a year, or three to five every day. The birds supplement their diet with rabbits, rodents, birds, and fish.
The snowy owl is a patient hunter that perches and waits to identify its prey before soaring off in pursuit. Snowy owls have keen eyesight and great hearing, which can help them find prey that is invisible under thick vegetation or snowcover. The owls deftly snatch their quarry with their sharp
These magnificent owls sometimes remain year-round in their northern breeding grounds, but they are frequent migrants to Canada, the northern United States, Europe, and Asia. Lemming availability may determine the extent of southern migration, when owls take up summer residence on open fields, marshes, and beaches.
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Aves
Emperor Penguins
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he freezing temperatures and strong snow storms that are expected during the bitter Antarctic winter, are not the most likely place you would expect to find animals breeding. However, when the temperatures begin to turn, hundreds of the world’s largest penguins begin to come together to breed. The emperor penguin, which is the only animal capable of withstanding the Antarctic winter on the open ice, can walk up to 120 km to get to its breeding
grounds. There can often be thousands of emperor penguins in one place, which serves a useful purpose when the females leave the males to look after the eggs while they go out to sea to gather food. Penguin Family The male penguins, with their precious eggs on their feet, spent much of the two months the egg takes to hatch, huddled together in order to keep warm as temperatures can drop as low as -40 degrees centigrade. The female penguins usually arrive
back from their fishing trip just after the eggs have hatched, and they take over caring for the chick while the males go out to sea. Penguin Diving The whole process of travelling, mating and incubating the egg, can take up to four months so its hardly surprising that a male emperor penguin can lose more than half his body weight in that time. Once the male emperor penguin has eaten, both the male and the female penguin take it in turns to look after their chick while the other goes out to fish.
Birds In Antarctic March 2013
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Fish
FISH
Sometimes it’s hard to tell what is a fish and what isn’t. A sea horse doesn’t look like a fish, but it is. And a dolphin looks like a fish, but it isn’t! The way to tell is if they have three things. Fins, scales, and gillsNearly all fish have scales. Some are little round or diamond shaped pieces of thin bony stuff. They fit together and cover the fish’s whole body. And nearly all fish have fins. A fish usually has a fin on its back, a fin on its belly, a broad fin for a tail, and two fins on each side. They steer themselves with the smaller fins and uses the tail fin to propel itself forward. And all fish have gills. Gills are the slits in a fish’s head, behind its mouth. Fish breathe through them. The gills are openings filled with thin pieces of skin, almost like the pages of a book. Water goes into the openings and through the “pages”. They take the oxygen out of the water and put the oxygen into the fish’s blood. Like all other animals, a fish needs oxygen to live..
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Fish
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The Pu T
he puffer fish (also known as the blowfish and the toadfish) is a medium-sized species of fish that inhabits warmer, coastal waters around the world. The puffer fish is most well known for it’s unique and distinctive adaptations that the puffer fish has to defend itself. There are around 120 known species of puffer fish, the second most poisonous creature on the planet after the Golden Poison Frog. The puffer fish is found in tropical waters worldwide, but they rarely go into the cooler waters. The puffer fish has the remarkable ability to expand its body extremely quickly when faced with danger, unavailing it’s long poisonous spikes that cover its body. If a fisherman catches a puffer fish, they will never touch the spikes as they are highly toxic to humans and animals. The puffer fish can grow to up to 60cm in length but the exact length of the puffer fish depends on the species of puffer fish. Puffer fish can be found in a variety of colours but can sometimes be hard to identify when they are not inflated. The puffer fish normally has the appearance of a large tadpole, with bulging eyes and an 24
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elongated snout. Puffer fish are omnivorous animals and eat a variety and plants and animals. Puffer fish mainly feed on the algae that grows on the rocks and coral and also the invertebrates that inhabit these areas. Large species of puffer fish will also eat shellfish such as shrimp and crabs and molluscs. Although there are a number of animals that prey on the puffer fish, these predators often meet with a nasty end. When the puffer fish is threatened it inflates it’s body with air exposing the long, sharp, toxic spikes which normally intimidates the predator into
retreating. If however, an animal does manage to eat the puffer fish, it will often be poisoned by the toxins in the spikes or the toxin that is released from the organs of the puffer fish when it dies. Despite the toxins in the puffer fish, some animals such as sharks are able to eat the puffer fish without becoming harmed. It is important also to know March 2013
uffer Fish
that not all species of puffer fish are actually poisonous and these species are preyed upon by larger fish, sharks and also humans. The smallest species of puffer fish in the world is the dwarf puffer fish (also known as the pea puffer fish and the pygmy puffer fish). The dwarf puffer fish is tiny growing to just an inch in length, which is a few March 2013
centimetres. Despite the fact that the dwarf puffer fish is related to larger species of puffer fish, the dwarf puffer fish is not found in the sea but in just one river in India. Not only does the puffer fish have unique defensive methods but they also have unique breeding methods. The male puffer fish guides the female puffer fish towards the shore where she releases between 3 and 7 eggs. The eggs of the puffer fish are extremely light and float on the surface of the
Fish
water until they hatch in about a week’s time. The puffer fish fry are still not fully developed and have a hard shell that protects them until their limbs begin to grow. The shell of the baby puffer fish then cracks off and the tail and fins develop. When the puffer fish is big enough, it will swim down and integrate itself into the reef community below. Despite the puffer fish having such a deadly venom, there are some species of puffer fish whose meat is eaten in Japan and Korea as a local delicacy. Special chefs are trained to cut the fish so that the fish does not poison the consumer. Other species of puffer fish produce and release a toxin into their organs when they die to harm the thing that ate them.
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REPTILES
Reptiles
Reptiles are one of the six basic groups of animals. Reptiles are cold-blooded vertebrates that diverged from ancestral amphibians about 340 million years ago. There are two characteristics that distinguished early reptiles from amphibians and enabled them to colonize terrestrial habitats more extensively than their ancestors, scales and the ability to lay hard-shelled eggs. Scales protect reptiles from abrasion and loss of body moisture. Hard-shelled eggs provide a protective environment in which the embryo can develop.
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Reptiles
Saving the World’s Most Endangered Sea Turtle
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ea turtles are found in all of the major oceans and smaller seas with the exception of the Arctic Circle as it is generally too cold for sea turtles as they tend to prefer more temperate waters. The bigger species of sea turtle are found more in the Southern Hemisphere in the tropical, warmer waters. There are 7 known species of sea turtle today including the flatback sea turtle which is native to Australia; the green sea turtle which is found all over the world but there are larger populations of the green sea turtle in the Atlantic and Pacific oceans; the hawksbill turtle is a critically endangered species of sea turtle and can be found all over the world; the kemps ridley turtle is the rarest species of sea turtle in the world and is found in the Atlantic ocean and in the Gulf of Mexico; the leatherback sea turtle is the largest species of sea turtle and is the most widely distributed species of sea turtle, found all over the world; the loggerhead sea turtle is known for it’s large head and is mainly found in the Atlantic, Indian and Pacific oceans; the olive ridley sea turtle is the smallest species of sea turtle and is generally found in the Indo-Pacific and Atlantic oceans.
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Although sea turtles spend their time out at sea, sea turtles always go back to the same beach to breed and often travel huge distances to get there. The female sea turtles bury their eggs in the sand on the beach where they were born. After laying her eggs the female sea turtle will return to the sea, leaving her eggs to hatch in their nest under the sand. When the baby sea turtles hatch, they walk straight into the ocean and begin their life at sea. Today, all of the 7 different species of sea turtle are under threat from extinction. The decline in the world’s sea turtle population is thought to be mainly due to the sea turtles being caught accidentally by large fishing boats and due to the fact that humans will often take the eggs of the sea turtle to eat as a delicacy. Numerous conversation projects are underway all over the world in order to try to protect and preserve the sea turtle populations that remain. The diet of the sea turtle depends on it’s particular species. Some species of sea turtle are carnivorous, others are herbivores and some species of sea turtle will eat almost anything. Sea turtles tend to eat sea grasses, shrimp, crabs, fish and jellyfish, depending on what the sea turtle can find and catch.
Sea turtles have the remarkable ability to travel hundreds (in some cases thousands) of miles in order to get between their feeding grounds and their nesting grounds. Most female sea turtles return to the same beach to nest every time and will often emerge from the water just meters away from from where they nested the time before. Sea turtles will often be able to breed for around 30 years with some species of sea turtle not being able to do so until they are 50 years old. Adult sea turtle have few natural predators besides large sharks and being caught up in human fishing nets meaning that they can live to more than 80 years old. Around 90% of baby sea turtles are eaten by smaller predators like raccoons, sea birds and large fish. Male and female sea turtles tend to be around the same size. Adult sea turtles vary a great deal in size depending on the species of sea turtle with the smallest sea turtles measuring around 50 cm and largest are nearly 2 m.
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Reptiles
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Reptiles
Science and the Environments Extreme ‘housework’ cuts the life span of female Komodo Dragons
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n international team of researchers has found that female Komodo Dragons live half as long as males on average, seemingly due to their physically demanding ‘housework’ such as building huge nests and guarding eggs for up to six months. The results provide important information on the endangered lizards’ growth rate, lifestyle and population differences, which may help plan conservation efforts. The Komodo dragon is the world’s largest lizard. Their formidable body size enables them to serve as top predators killing water buffalo, deer and wild boar and they have also been known to kill humans. A research team which included scientists from the University of Melbourne, Australia, Indonesia and Italy studied 400 individual Komodo Dragons for 10 years in eastern Indonesia, their only native habitat. The team then produced a model of the Dragon’s growth rate, with results published in the current issue of international journal PlosOne.
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Males live to around 60 years of age, reaching an average 160 cm in length and 65 kg at adulthood. However their female counterparts were estimated to live an average of 32 years and reach only 120 cm in length, and 22kg. Dr Tim Jessop from the Department of Zoology at the University of Melbourne was a co-author on the study and said that the team were surprised by the significantly shorter lifespan of the female Komodo Dragon. “The sex-based difference in size appears to be linked to the enormous amounts of energy females invest in producing eggs, building and guarding their nests. The process can take up to six months during which they essentially fast, losing a lot of weight and body condition, he said. “Males and females start off at the same size until they reach sexual maturity at around seven years of age. From then on females grow slower, shorter and die younger.“
of the Komodo Dragons as this critical process can indicate how the species prioritises its energy use in lifestyle and reproductive strategies. The results suggest that females have high energy ‘costs’ for reproduction resulting in their smaller size, whereas to reproduce successfully, males must keep increasing in size. The results could have dramatic consequences for the endangered species as early female deaths may be exacerbating competition between males over the remaining females, possibly explaining why males are the world’s largest lizards. “These results may seem odd to humans when the life span between Australian men and women differ by five years. But each species has different strategies to pass on their genes. For example humans invest a lot of energy in few children as raising them is very energy intensive, whereas insects will have hundreds of offspring with no input into their rearing.”
The research team was keen to understand the growth rate
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EDITORIAL Editor in Chef: Elderton Stocks Managing Editor: Gilmar Wendt Senior Editor: Mike Hall Reporter: Matthias Ernstberger Visual Editor: Stefan Sagmeister Graphic Designer: Vincent Surya Photo Editor: Scott Marble Photographer: Arianne Van Lewis Editorial Secretary: Ian Chilvers Office Boy: Bill Cahan PUBLISHING Publisher: Benjamine Morrison Bussines Director: Adam Giles Bussiness Vice Director: Jim Sutherland Advertising Manager: Harriet Devoy Advertising Director: Steve Royle Advertising Sales Executive: Mick Thorpe Promotion Manager: Justin Smith Promotion Executive: Michael Braley Distribution: Vince Frost Production Director: Ray Parslow Production: Harry Pearce
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