The platypus is a unique animal that lives in Australia. Although it lays eggs like a bird, it's a mammal. A platypus mother feeds her babies with milk from her body. The platypus spends much of its time in the water. It paddles with its front feet and steers with its back feet. The platypus scoops through the sand with its bill in search of worms and small water animals that it eats. The male platypus has sharp spurs and venom sacs on its back feet. It can scratch its enemies and poison them with its venom.
She's gotta have it
She's gotta have it Evolutionary biologists are exploring the question
of why females of many species are attracted to the most colourful
males, and if these bright colours signal a male's quality.
Biologists think that the answer lies in the energy needed to grow
a colourful coat or plumage. It is suggested that only the
healthiest males with the best genes have the energy to display and
maintain the brightest colours, thus displaying their worth to
possible mates. Pigments called "carotenoids" help birds to achieve
bright plumage. Many of these pigments are gained by eating insects
which contain them. Biologists argue that only the fittest birds
would be able to find and eat enough of these insects to gain the
brightest plumage. Carotenoids found in the insects are also
important for immune defence and detoxification, so the brightest
males could indeed be signalling their evolutionary
worth. JANUARY 29, 2000, P. 22-26
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