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Crabs evolved at least five times from separate groups of crustaceans (2021)

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Re: Crabs evolved at least five times from separate groups of crustaceans (2021)

#61

Post by mirekrusin »

version_five wrote: post #21
samatman wrote: post #15

Even more wild to me is that saber-toothed cat-like predators evolved seven separate times: https://en.wikipedia.org/wiki/Saber-toothed_predator

There was a recent article on here about how species that looked alike were not necessarily related and is was more common to have physically dissimilar but geographically close species that were evolutionary relatives. One of the points was that convergent evolution was more common than people thought. These stories appear to support the convergent evolution assertion

I wasn't aware of that some time ago, it's a fascinating insight.

I got a lightbulb (going wtf/dark actually!) when watching cartoon or something with triceratops. They looked so much like rhinos. But had eggs. I had trouble reconciling it with evolution. They were so far ancestor-wise but so close physically-looking wise. Convergent evolution is very interesting.

It suggests aliens may not be that different from us after all, if exist.

Re: Crabs evolved at least five times from separate groups of crustaceans (2021)

#62

Post by Spixel_ »

alluro2 wrote: post #54
AlbertCory wrote: post #16

> We know the process has occurred multiple times and our current grant is aimed at better understanding the drivers and implications What can they actually discover? 10 legs good? But how about 12? [1] > The crab with the longest legs is the Japanese spider crab. It’s not related to spiders, despite its name. When extended, its legs can be as long as 12 feet. Now there's a nightmare for you. [1] https://www.referenc…

Oh that's some nightmare fuel all right: https://en.m.wikipedia.org/wiki/Japanese_spider_crab#/media/...

You should play Obra Dinn.

Re: Crabs evolved at least five times from separate groups of crustaceans (2021)

#63

Post by ativzzz »

mirekrusin wrote: post #61
version_five wrote: post #21

Earlier quoted context omitted.

There was a recent article on here about how species that looked alike were not necessarily related and is was more common to have physically dissimilar but geographically close species that were evolutionary relatives. One of the points was that convergent evolution was more common than people thought. These stories appear to support the convergent evolution assertion

I wasn't aware of that some time ago, it's a fascinating insight. I got a lightbulb (going wtf/dark actually!) when watching cartoon or something with triceratops. They looked so much like rhinos. But had eggs. I had trouble reconciling it with evolution. They were so far ancestor-wise but so close physically-looking wise. Convergent evolution is very interesting. It suggests aliens may not be that different from us…

> It suggests aliens may not be that different from us after all, if exist.

Alternatively, they are the more evolutionally convergent species and we will evolve towards something inhuman

Re: Crabs evolved at least five times from separate groups of crustaceans (2021)

#64

Post by bobbylarrybobby »

pratik661 wrote: post #37

Ive always wondered this: has a species have an evolutionary history where they originated in land but adapted to living in water and then adapted to living on land again?

Well, there's the https://en.wikipedia.org/wiki/Aquatic_ape_hypothesis but I think it's generally written off by "actual" scientists.

Re: Crabs evolved at least five times from separate groups of crustaceans (2021)

#65

Post by docmechanic »

version_five wrote: post #21
samatman wrote: post #15

Even more wild to me is that saber-toothed cat-like predators evolved seven separate times: https://en.wikipedia.org/wiki/Saber-toothed_predator

There was a recent article on here about how species that looked alike were not necessarily related and is was more common to have physically dissimilar but geographically close species that were evolutionary relatives. One of the points was that convergent evolution was more common than people thought. These stories appear to support the convergent evolution assertion

Here's another: https://www.sciencedaily.com/releases/2022/06/220601111749.h...

"They found that the animals grouped together by molecular trees lived more closely together geographically than the animals grouped using the morphological trees."

Re: Crabs evolved at least five times from separate groups of crustaceans (2021)

#66

Post by r930 »

kjeetgill wrote: post #14

Eons did a great piece on this recently: https://youtu.be/wvfR3XLXPvw One of the things I love about the way Eons cover topics is how they don't just focus on what we know, but also how we know, who figured things out, and what we got wrong along the way. Can't endorse their style of science journalism enough.

Anton Petrov did a nice video on the subject also: https://youtu.be/tWq3IrO9K3U

Re: Crabs evolved at least five times from separate groups of crustaceans (2021)

#69

Post by micro_cam »

pratik661 wrote: post #37

Ive always wondered this: has a species have an evolutionary history where they originated in land but adapted to living in water and then adapted to living on land again?

The Hawaiian nene goose has become mostly terrestrial and is loosing its webbing.

Re: Crabs evolved at least five times from separate groups of crustaceans (2021)

#70

Post by throwaway742 »

gibolt wrote: post #17
samatman wrote: post #15

Even more wild to me is that saber-toothed cat-like predators evolved seven separate times: https://en.wikipedia.org/wiki/Saber-toothed_predator

The teeth are already there. A few gradually longer ones makes obvious sense to be a better predator, giving them an evolutionary advantage.

Then why aren't they still around? Why don't they evolve again?
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