The platypus unravelled

[Countess Olenska]

The platypus unravelled (http://www.cosmosmagazine.com/node/1970)

http://www.cosmosmagazine.com/files/imagecache/feature/files/20080507_platypus.jpg

It's been an enduring mystery since Western science 'discovered' it 200 years ago, but the publication of the platypus genome is now giving us an unprecedented insight into this perplexing hybrid of mammal and reptile.
Who would think that the reclusive platypus would be such a trouble-maker? When the antipodean oddity made its British debut in 1799, it stirred up a ferocious debate that lasted 85 years; one that Darwin himself didn't even see the end of.
At first naturalists thought the furry creature with the webbed feet and the duck's bill was a hoax, the work of a skilful Chinese taxidermist. A specimen in London's National History Museum bears the scars of an attempt to unpick the fine 'stiches'. When none were found, the debate turned to whether this creature was really a mammal at all. Though furry, no nipples or mammary glands were visible.
Even more perplexing, dissection showed a single lower body opening like the cloaca of a bird or reptile. That earned it, and its similarly equipped cousin the echidna, a new classification amongst mammals: the 'monotremes'.
Mammary glands were located in the 1830s. But it took till 1884 for William Caldwell's famous telegram "Monotremes oviparous, ovum meroblastic," to reach the gobsmacked naturalists of the British Association for the Advancement of Science. What the young Scottish embryologist had telegraphed was: the platypus laid eggs and they were yolky. There it was: a furry, suckling, lizard-limbed, egg laying mammal. Who could resist the temptation to see it as a missing link between reptiles and mammals? Darwin, even without the egg-laying information, pronounced: "these anomalous forms may almost be called living fossils."
Now, some 209 years after the platypus first confounded the scientific community, the U.K. journal Nature has published a detailed analysis of the creature's genome; its genetic blueprint revealed in 2.3 billion letters of DNA code.
More at link....http://www.cosmosmagazine.com/node/1970

[Countess Olenska]

I thought it was neat how it was more or less a mid evolution creature. Part reptile and part mammalian but with genetic code more like crossing a chicken with a reptile. An evolutionary hiccups in genetic DNA or a weird mutant that defies all laws. How can you have DNA that is identical to a chicken and to live, births with placentas and milk production? What about venom like a reptile that has antimicrobial properties of mothers milk?

Curiouser and curiouser...Just thinking about it made me have dreams of a lactating t-rex with chicken feathers popping out live babies!

[swivel]

Something to keep in mind:

There have literally been billions of transient species, which had many of the features of relatives on either side. Normally, however, such species die out very quickly. They are attempting to compete with animals in identical niches that have greater evolutionary stability. They are like scaffolding in construction.

I'm not pretending that evolution "knows" where it is going, nor that it progresses in a steady direction towards some greater goal, but it is hard to talk about the history of evolution without having your comments drip with such bias. We tend to make the mistake of seeing competition between animals as something that takes place between distant species... such as the lion and the antelope. In reality, that duo enjoys a symbiotic relationship of sorts. True competition takes place within a species and the species closest to it. They are vying for the same resources (and mates). It wasn't long after our predecessor took our current form that all other homo varieties disappeared. Perhaps into our tummies!

The miracle of the Platypus isn't one of existence, it is one of survival. There have been countless amalgamations of various genera in the past... but most of them are not as efficient in their niche as some later modification.

Great find, mammasweets.

[impqueen]

i've always found the platypus and the echidna really interesting and fun to study.

Thanks for the link!

[Lizard]

Australian researchers have now uncovered the evolutionary basis of one of its most unusual features: its venom.

Both male and female platypus (Ornithorhynchus anatinus) are born with hind leg spurs, but only males produce a cocktail of venom there, which helps them compete with other males for mates and defend themselves against predators. The venom is powerful enough to kill dogs and though it is not fatal to humans, it can cause pain so intense that the victim is debilitated for weeks.

Venom! I had no idea!

http://www.cosmosmagazine.com/node/1423

[CPL CHUD]

Haven't they also found vestigal limbs on some whales? It's rare to find those transient species that connect the dots so to speak. History has covered up so much about our own family tree. I think that the total amount of bones uncovered of our own ancient ancestors number less than what fits in the back of a normal pick up. Any new discovery is exciting to me.

[Countess Olenska]

Haven't they also found vestigal limbs on some whales? It's rare to find those transient species that connect the dots so to speak. History has covered up so much about our own family tree. I think that the total amount of bones uncovered of our own ancient ancestors number less than what fits in the back of a normal pick up. Any new discovery is exciting to me.

I completely agree. It's like reading a book with pages missing.