Thursday, May 8, 2008

So why the considerable ability to sense odors?


Platypus are capable of many vocalisations including a soft growling sound when disturbed. audio buttonHave a listen this rarely heard growl!

PARIS (AFP) — Arguably the oddest beast in Nature's menagerie, the platypus looks as it if were assembled from spare parts left over after the animal ...The platypus (Ornithorhynchus anatinus) is an odd-looking creature whose features combine the furry torso and wide, flat tail of a beaver with the rubbery bill and webbed feet of a duck. But its looks are not all that is strange about it. A new study indicates that the distinctive mammal's genetic code is an eclectic brew of bird, reptile and mammal.
This mix-and-match animal is more than just an oddity, though. Researchers report in Nature that its genome provides important clues into how mammals, birds and reptiles evolved from a common ancestor some 315 million years ago. And researchers at Stanford University School of Medicine report in Genome Research that they linked the evolution of a gene in the old platypus to a mutated version in humans responsible for moving the testes outside of the body and into an external pouch, or scrotum.http://www.sciam.com/article.cfm?id=whats-our-connection-to-t
The scientists speculate that it may involve sexual communication
or the use of water-soluble odorants in navigating and hunting underwater.“As weird as this animal looks, its genome sequence is priceless for understanding how mammalian biological processes evolved.”“What is unique about the platypus is that it has retained a large overlap between two very different classifications, while later mammals lost the features of reptiles,” Dr. Warren said in an interview.In their investigation of the platypus genetic blueprint, the scientists found that its genome contains about 18,500 genes, similar to other vertebrates and about two-thirds the size of the human genome. The platypus shares 82 percent of its genes with the human, mouse, dog, opossum and chicken. Some repeated elements in the genome, the scientists noted, hold hints as to the chronology of changes in the platypus
.Of particular interest, the researchers reported, the analysis identified families of genes that link the platypus to reptiles (like those for egg-laying, vision and venom production), as well as to mammals (antibacterial proteins and lactation). The platypus lacks nipples; the young nurse through the abdominal skin.http://www.nytimes.com/2008/05/08/science/08platypus.html?em&ex=1210478400&en=b48172a60cb5cf9f&ei=5087%0A

Which is the greater mystery: the breeding habits of the platypus or the workings of the human heart?

In 1883 young British naturalist William Caldwell arrives in Australia with a mission: to determine for the scientific record whether platypuses really are egg-laying mammals. But first he must travel overland to the Burnett River in Queensland, where he intends to set up camp. On his journey he is by turns hindered and assisted by a cast of characters, including a drunken bullocky and an inscrutable, poetical bushman. Once there, William commences his investigations and encounters the local Aboriginal people, enlisting their help and ultimately learning their tragic history. He also meets a young blind woman with many closely held secrets of her own.

Love and the Platypus is a delightful, captivating novel that examines the obsessive nature of scientific enquiry and its environmental consequences, and the wonders of nature and of romantic love.http://www.scribepublications.com.au/book/loveandtheplatypus

Genome analysis of the platypus reveals unique signatures of evolution
http://www.nature.com/nature/journal/v453/n7192/full/nature06936.html
http://www.dpiw.tas.gov.au/inter.nsf/WebPages/BHAN-53573T?open

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