evolutionary "leftovers" on humans

[Smallville]

nictitating membrane of the eye;
.

what was the purpose of that one?

http://en.wikipedia.org/wiki/Nictitating_membrane

gives you a good explanation.

[Smallville]

I know it's not really a throw back, more like a developing trait but we are the only primate with webbing between our fingers, with the really big coincidence that we are the only primate that swims.

really inteersting. Maybe im some point in our evolution, we lived near the beach, or something similar.

The Proboscis Monkey swims. So does the Allen's Swamp Monkey. There's probably others.

[crocofish]

There is a book published this year called Your Inner Fish.  It discusses how our human anatomy evolved from the fish, including the evolutionary relics.  It is on my "to be read eventually" list.  And the critter on the cover is Tiktaalik, my avatar.

[Loffler]

Um, hello? The appendix?

[Loffler]

I know it's not really a throw back, more like a developing trait but we are the only primate with webbing between our fingers, with the really big coincidence that we are the only primate that swims.

http://en.wikipedia.org/wiki/Aquatic_ape_theory

[MariaEvri]

nictitating membrane of the eye;
.

what was the purpose of that one?

http://en.wikipedia.org/wiki/Nictitating_membrane

gives you a good explanation.

I knew that birds and sharks had this but I had no idea we had that too
thats really great stuff

[MariaEvri]

There is a book published this year called Your Inner Fish.  It discusses how our human anatomy evolved from the fish, including the evolutionary relics.  It is on my "to be read eventually" list.  And the critter on the cover is Tiktaalik, my avatar.

Thanks for the link. This will go in my "to buy" list

[Loffler]

http://en.wikipedia.org/wiki/Human_vestigiality

Humanity's junk drawer

[MariaEvri]

http://en.wikipedia.org/wiki/Human_vestigiality

Humanity's junk drawer

very useful thanks

[Tanker]

MariaEvri wrote:
Tanker wrote:
I know it's not really a throw back, more like a developing trait but we are the only primate with webbing between our fingers, with the really big coincidence that we are the only primate that swims.

really inteersting. Maybe im some point in our evolution, we lived near the beach, or something similar.

The Proboscis Monkey swims. So does the Allen's Swamp Monkey. There's probably others.

I should have been more specific and said ape, good catch though that statment was a bit misleading.I do know that  a family of chimps has been observed sitting in shallow pools (2 or 3 feet) of water to beat the heat but most apes stay away from deep water.

[shedaytrips]

How about your spleen.

[MariaEvri]

How about your spleen.

hmm I thought that was still used? XD

[Loffler]

How about your spleen.

hmm I thought that was still used? XD

It is, but like many organs it's redundant. There's a lot of redundancy in our organs.

[myleviathan]

How about your spleen.

hmm I thought that was still used? XD

The spleen is used for blood storage and for immune functions. You can live without it but your body's ability to fight off viral/bacterial infection would be compromised. The appendix is thought to play an immune function, as well. Kind of like Peyer's patches in the small intestine.

[rlrose328]

How about your spleen.

The spleen makes insulin which is instrumental in removing glucose from the blood stream.  If the glucose isn't removed (and no other organ does that job), you are at risk of developing neuropathy, blindness, and other complications.  No insulin = diabetes.

So... I don't think the spleen is either a leftover or redundant.  Unless my diabetes education these past 20 years has been deficient, there is no other organ that makes insulin... if there were, I wouldn't have neuropathy in my feet (one foot is slightly numb and the other is constantly tingly).