Does convergent evolution falsify evolution?

[Chrypt]

Hello everyone, 

I was reading the article +29 evidence for macroevolution on talkorigins.org and I've found that a potential falsification of the theory of common ancestor is to find an organism that have some common trait that evolved independently on two different clades.... Some examples would be :  a mammal with wings, a bird with mammal glands etc.... 

 

Some creationists claim that this is already the case.... And scientists calls it 'convergent evolution'...they give many examples for some placental mammals and marsupial mammals taht they look so much alike more than the other species of the clade where they belong to. 

A thylacine, for instance its skull looks exactly like a dog's skull.. And yet, scientists consider thylacine to be more related to a kangaroo than to a dog. 

 

Is that really a falsification of the nested hierarchies that are predicted by evolution from common ancestors? 

 

 

 

 

[Strange]

5 minutes ago, Chrypt said:

I've found that a potential falsification of the theory of common ancestor is to find an organism that have some common trait that evolved independently on two different clades.

This is pretty common. The eye, for example has evolved multiple times and can be very similar in species that are very distantly related (humans and octopuses, for example). This is exactly what you would expect from evolution.

10 minutes ago, Chrypt said:

Some creationists claim that this is already the case....

This is, presumably, what is known as a "straw man" argument. Claim the theory says something that it doesn't and then show that your false version of the theory is wrong.

12 minutes ago, Chrypt said:

Is that really a falsification of the nested hierarchies that are predicted by evolution from common ancestors? 

No.

[Chrypt]

2 minutes ago, Strange said:

This is pretty common. The eye, for example has evolved multiple times and can be very similar in species that are very distantly related (humans and octopuses, for example). This is exactly what you would expect from evolution.

 

I agree...But an octopus eye and a human eye have a different design. Evolution from a common ancestor predicts such thing. 

On the other hand,  the thylacine and dog have exactly the same skull (same design) and yet.... Thylacine are more closely related to a kangaroo (kangaroo's skull is so much different than a Thylacine......Creationists claim that even if we have found a bird with mammal glands evolutionary biologits will hide behind the "convergent evolution theory" which makes evolution unfalsifiable. 

When should we consider a similar trait a homology and when should we consider it a convergent evolution.... What if someone claimed that a thylacine is just a dog that had developed a marsupial pouch? And wasn't the other way around? 

Maybe I sound funny... I do accept evolution... But I guess sometimes it needs so much intelligence to reveal creationist's fallacies...

[Strange]

12 minutes ago, Chrypt said:

But an octopus eye and a human eye have a different design.

Neither of them have a design. Both evolved for a function. There are a limited number of ways to fulfil that function and so it is not surprising that completely different organisms have come up with similar solutions.

13 minutes ago, Chrypt said:

On the other hand,  the thylacine and dog have exactly the same skull (same design) and yet....

Presumably because they evolved to meet similar requirements - strong jaws for hunting and eating prey, eyes set forward (for hunting, again), etc.

17 minutes ago, Chrypt said:

Creationists claim that even if we have found a bird with mammal glands evolutionary biologits will hide behind the "convergent evolution theory" which makes evolution unfalsifiable.

It doesn't really matter what creationists say as they are either ignorant or dishonest. Or, in some cases, both. 

16 minutes ago, Chrypt said:

What if someone claimed that a thylacine is just a dog that had developed a marsupial pouch?

You don't classify organisms by looking at just one or two traits. 

[poo thrower]

it's the way genes work, you have "convergent evolution" because there is the consideration of recombination of genetics at some point in time and also independant assortment of genetics (inclusive of recessive traits etc) thereafter - it's about it's family tree vs it's evolution to reference point of today.

(yes i agree that a thylacine is blatently "more dog than kangaroo"... but that's an argument between "choice of two animals", not the bits they are comprised from)

https://www.khanacademy.org/science/high-school-biology/hs-classical-genetics/hs-introduction-to-heredity/a/the-law-of-independent-assortment

Edited February 5, 2020 by poo thrower

[zapatos]

4 hours ago, Chrypt said:

On the other hand,  the thylacine and dog have exactly the same skull

Are you saying that if presented with a thylacine skull and a dog skull, there is no test that could differentiate between them?

[Ken Fabian]

Thylacyne skulls are quite distinct from Canine - competent experts won't have any trouble telling them apart. Especially the teeth, which for a Thylacine, are distinctly marsupial. Thylacine teeth are not well evolved for crunching bones.

It is worth keeping in mind that marsupials and mammals do share much in common; evolution will make variations around what already exists and works.

Edited February 9, 2020 by Ken Fabian