Who are the ancestors of the Duckbilledplatypus?

Question

Lays reptilian eggs
Bill of a duck but SOFT AND SENSETIVE enough to feel a worm under water on the river bed with its eyes closed.
Poisonous barbs on its feet in the mating season only.
Feeds young with no nipples just milk running down its fur which is lapped up by young.
Fur like a mammal but waterproof.
Pockets in its jaw to store food.
Reptilian like shoulder girdle.
Intricate nervous system and a large cerebral vortex which suggests high intelegence.
ALMOST impossible to rear in captivity.

These are just some of it's contradictory features. How do we correlate this with evolution theory?

MY QUESTION IS FOR PEOPLE WHO DON'T UNDERSTAND.

TRANSITION FROM WHAT? lol

Answer 1

the little beast remains a mystery for all manner of science! I think they are cute. But I have no idea how to classify them. Let's just call them 'alien life forms' for the time being. :)

Answer 2

These are not contradictory features. In fact, they are only logical when viewed in light of evolutionary theory, it is only from an 'intelligent design' or Creationist perspective that these features are inexplicable.

The egg-laying characteristic of the monotremes (including the modern platypus and echidnas) is a hold over characteristic from the reptilian ancestors of all mammals. The monotremes are representatives of a type of mammal that existed before either the marsupial or the placental mammalian method of reproduction evolved. They managed to survive in Australia because there was an ecological niche there that actually made this egg-laying character an advantage.

While the platypus' bill looks superficially duck-like, structurally it is quite different, and the skull of the platypus is very definitely mammalian. The bill shape is one that is well suited to grubbing about in muck for worms and other tasty morsels, and so it is not surprising that it has appeared in many distinct, not even vaguely related evolutionary lines. This is something known as convergent evolution, where similar selection pressures and ecological niches result in superficially similar, but evolutionarily non-homologous structures.

The poisonous barbs are a unique character of the platypus, but aren't an evolutionary conundrum. There are other venomous mammals (including shrews, and possibly even hedgehogs).

The milk patch, with no nipples is another 'primitive' character, that might be expected from a group that branched off the mammal tree early in their history. It is quite fitting with the primitive reproductive system. It still works for them.

Pockets in the jaw are another common mammalian trait, that seem to come along with the development of cheeks.

Again, the reptilian-like shoulder girdle is not that surprising considering this is an anatomically primitive group of mammals. It shows the evolutionary link between mammals and reptiles. This would make it one of those transitional forms that Creationists always claim don't exist.

The nervous system and cerebral cortex are larger than those seen in most reptiles, but are fairly small for a mammal. Again, this would appear to be one of those transitional traits that Creationists allege don't exist.

Yes, they are nearly impossible to rear in captivity, but there are a lot of critters like that, from manta rays to cheetahs (not impossible to raise, just hard to breed). There is nothing contradictory or evolutionarily perplexing about this trait, it has more to do with the species' individual temperament and ecological requirements.

When you include fossil evidence of earlier ornithorhyncoids, which did have teeth, and earlier fossils of platypus found in places like South America (where they went extinct having to compete with placental mammals), it all fits pretty much exactly what would be predicted by evolutionary theory.

The anatomy, physiology and fossil history of the platypus actually strongly supports evolution. No contradictions or correlations necessary.

Answer 3

The oldest discovered fossil of the modern Platypus dates back to about 100,000 years ago, during the Quaternary period. The extinct monotremes (Teinolophos and Steropodon) were closely related to the modern Platypus.[41] The fossilised Steropodon was discovered in New South Wales and is composed of an opalised lower jawbone with three molar teeth (whereas the adult contemporary Platypus is toothless). The molar teeth were initially thought to be tribosphenic which would have supported a variation of Gregory's theory, but later research has suggested while they have three cusps they evolved under a separate process.[14] The fossil is thought to be about 110 million years old, which means that the Platypus-like animal was alive during the Cretaceous period, making it the oldest mammal fossil found in Australia. Monotrematum sudamericanum, another fossil relative of the Platypus has been found in Argentina, indicating that monotremes were present in the supercontinent of Gondwana when the continents of South America and Australia were joined via Antarctica (up to about 167 million years ago).[14][42]

Because of the early divergence from the therian mammals and the low numbers of extant monotreme species, it is a frequent subject of research in evolutionary biology. In 2004, researchers at the Australian National University discovered the Platypus has ten sex chromosomes, compared to two (XY) found in most other mammals (for instance, a male Platypus is always XYXYXYXYXY). Furthermore, one of the Platypus' Y chromosomes shares genes with the ZZ/ZW sex chromosomes found in birds. This news further pronounced the individuality of the Platypus in the animal kingdom.[43] However it lacks the mammalian sex-determining gene SRY, meaning that the process of sex determination in the Platypus remains unknown.[44]

Answer 4

For anybody who has an awareness of natural history the characteristics you mention are hardly remarkable. Animal species have all kinds of unique adaptations to help them survive in their habitat and far from providing a challenge to evolutionary biologists they only serve to confirm the fact of natural selection. The fossil record alone gives a comprehensive record of the transitional stages of monotremes and contains evidence of species which are related to the Platypus. As usual the creationists have the wrong end of the stick- they see only problems where there is in fact compelling evidence to support evolution.

Answer 5

The monotreme family, which includes both the echidna and the duckbilled platypus, are predicted by the theory of natural selection. You guys want LIVING transitional forms -- there you go.

Answer 6

Who are ancestors? What about my mother in law. Reptilian? Dragon like creature - that's her to a tee lol

Answer 7

Why would you ask a question for "people who don't understand"?

Answer 8

a long long time ago a duck and a beaver got really really drunk.

Answer 9

wish i was one

Answer 10

http://en.wikipedia.org/wiki/Platypus#In_mammalian_evolution

Look it up