I am a steadfast believer in the theory of evolution, BUT .....?

Question

... what’s the deal with our good friend, the nautilus? More than 500 million years has passed over it without essentially any evolutionary effects, whatsoever!!! ... Is the nautilus such a perfect experiment in evolutionary design that it hasn’t required Nature's tweaking in all this time?

Answer 1

it don't need to be fixed and you can't win with mother nature

Answer 2

evolution means that if a new generation has some better traits (in terms of improving chances of survival, and thus of reproduction), then it will survive better and those traits will spread through the species.

however if after a long period of time a species has, by this process, adapted optimally for its environment, and the environment does not change, it is quite possible that the species will not evolve much anymore, or not at all.

there are tons of examples: many bacteria (millions of them), the nautilus, sharks, crocodiles, tortoises, you name it. These species most probably continue to undergo minuscule mutations, but apparently none produce an improvement that is visible enough. Over a hundred million years the sharks have, at most, optimised their teeth a bit, and "adopted" simpler and less numerous fins which probably saves on the development cost.

capitalist business is also supposed to select the best adapted firms, while the lesser performers end up starving (not having enough cash). So you could say, well, if that's true, then why has Microsoft largely not evolved for the past 15 years or so? Well, because it is so well adapted to its niche, so dominant, and because the environment is not really changing.

hope this helps

Answer 3

Read up on "punctuated equilibria". Basically, if a species is very well adapted to its ecological niche, there's no reason for it to change. Any mutation will be less well adapted to its environment, so the mutations die off and the species remains unchanged.

The fossil record shows evidence of long periods of critters not changing much, followed by some cataclysmic event (like a meteor impact causing mass extinction) that radically alters the ecological landscape. After the cataclysmic event, there's a great deal of evolutionary change as species adapt to fill new ecological niches, or niches that have been vacated by some other critter that went extinct.

There are many examples of species that haven't changed in over a hundred million years. There's nothing bizarre about that, it just means those species were extremely well adapted to their ecological niche, so there was no evolutionary pressure to change. The Nautilus isn't "perfect" (there's no such thing as perfection), but it's extremely well adapted to its ecological niche, and that niche has been very stable for a very long time.

Answer 4

The nautilus has indeed changed over millions of years. However, we have a difficult time seeing these changes if they aren't large and external. For example, if the nautilus has evolved in response to a gradual change in the salinity of ocean water over several thousand years, we wouldn't notice unless we did detailed genetic analysis. As some of the other answerers have pointed out, the nautilus also fills its current role in the ecosystem (a term biologists call a "niche") well and so hasn't needed to make large, noticeable changes to its body or behavior.

Answer 5

There are some organisms that have changed very little over long periods of time. Sharks and alligator/crocodiles are another example. What is required is a stable environment and organisms will evolve to survive in that environment. Then, little change is necessary for the species to survive thousands or millions of years unchanged.

So in short, if not perfect the nautilus is well suited for its habitat.

Answer 6

The nautilus hasn't changed much, but it's not really dominating the planet right now either...

Answer 7

The environmental pressures are insufficient to require them to adapt and change. In short, they indeed have stumbled onto an almost perfect design for their niche.

Answer 8

hey, i am a hardcore creationist....my problem stems from the duckbilled platypus. a warm blooded mammal that not only has a duckbill, but also lays eggs and the male has a poison appendage.....

robin williams said God must have really been high to create that one....i think He put it here to show us christians, who happen to be scientists as well, that we have not figured it all out, yet.

--eagle

Answer 9

How do you know it's 500 million years old?

Answer 10

If there is no need to change in order to survive, nature wont do it.