Evolutionists..Why is it that some things evolve and some don't.?

Question

This will likely show how ignorant I am but

I'm wondering why gators, for instance, haven't changed much over millions of years.

And if a species is so adaptable/durable/well suited and if the ice caps are melting then could humans ever become more like gators (hypoth/supposing nothing interferes? )

If the earth continues to support life for millions of years more (with all else progressing at the same rate as now) what is said about what humans might look like?
1 second ago - 3 days left to answer.

Answer 1

Mutations happen slowly. If a mutation improves the species, the mutated animal will have more success, and will reproduce more. This increases the odds of the 'positive' mutation leading to an evolutionary change.

If no mutation improves the species, little change will happen.

Regarding gators, for instance...

...the fossil record shows they used to be quite a bit larger. They've evolved to a smaller size to better suit their environment and food supply.

Regarding humans...

...we have mutations as well...like athletes and artists. If sports stars and rock stars keep having kids at a rate far beyond what 'typical' people do, the athletic and creative mutations responsible for their success will be encouraged.

On the flip side, those who are not having children at all for whatever reason offer little chance of their gifts (mutations) being passed on at all.

Think about it!

Answer 2

So many errors here it's actually hard to know where to begin. I'll have to limit it to bullet points. 1. Everything evolves towards a goal? No. Working towards a goal denotes planning and foresight, evolution has neither it is not a conscious entity it is a process. Evolution must work every step of the way, there is no goal. It is essentially playing it by ear. 2. Giraffes decide to grow long necks. No, if that was true I think most guys would decide to grow a certain part of their anatomy. If only it was that easy. Evolution takes place in populations over time, not individuals. There is no conscious choice in the matter. How it actually works is like this: Some giraffes have slightly longer necks than others (the same way not all humans are the same height) and having a longer neck means you are more likely to live because you can reach higher branches. If you are more likely to live due to your long neck, you are more likely to pass on the genes that gave you a long neck in the first place. So your baby giraffes have long necks. Your shorter necked counterparts die out. So there is a gradual trend to longer and longer necks, the average neck length goes up. This might take tens, hundreds or even thousands of generations, but the neck of the average giraffe get's longer. 3. Why do we engage in sexual reproduction? Singled celled organisms reproduce asexually as you correctly observed. This has it's advantages and disadvantages. The advantage is, as you observed, you don't need a mate. You just clone yourself. The problem with this is you have very limited genetic variation within the population, but that's OK if you can do a lot of reproducing. You compensate for lack of variation by sheer mass production. That works for single celled organisms. Metazoans like us cannot do that. We couldn't reproduce like bacteria if we wanted to we're too big and complex. We can't do asexual reproduction like they can. Sexual reproduction works for us because having a mate allows for genetic recombination, You get a lot more variation with limited numbers of offspring. We need a different method of reproduction because we are different. It's that simple.

Answer 3

Everything evolves, the gators today are not the same 'gators' that lived millions of years ago, modern gators have changed and adapted to the environmental niche they live in today, they would not have been able to survive in the same environment their ancestors did. Birds, Fish, Mammals, everything evolves, some creatures and plants evolve more slowly than others due to the fact they are so well suited for their environment and their environment changes very little. Get a real book on evolution and how it works and really read it.

Answer 4

Most things only show significant signs of change when there are harsh environmental pressures.

Alligators (and sharks) /have/ evolved but the changes are somewhat un-noticable at first glance. Even coelacanths have evolved to be different to their prehistoric counterparts.

Your question about humans - it's unlikely that we'll change much for a long time. We're supported by technology and medicine and can, for the most part, survive harsh environmental conditions. The main thing that's likely to happen is the species - unlimited in its movement - will become more homogenised over time (sorry to suggest - think the future people "goobacks" from South Park). Disease is also likely to shape us the way malaria has for bloodlines carrying sicklecell anemia.

Besides all that, even if we do change slightly or greatly, we'll still consider ourselves human.

Answer 5

There's no reason for gators to evolve.

That is, any mutations any have are more likely to make them less suited to survive, so those individuals die without reproducing. As long as they are in an environment where they thrive, there's no environmental pressure for them to evolve.

Global warming is a really fast process, evolution takes tens of thousands of years.

We wouldn't become gators. If we do evolve (which I think unlikely, partly because we thrive, partly because we're too numerous and spread out for any advantageous mutation to spread throughout the population), it wouldn't be into some other, existing creature.

Evolution builds on the existing body-design of living things.

Here's a web site for you about evolution, if you want to learn more.

You don't seem to understand it very well. It's really interesting stuff. There are also a lot of books that explain it -- books that were written for the general public, that don't assume a lot of science knowledge.

http://evolution.berkeley.edu

Answer 6

The basic crocodilian form is well suited for wetlands. The vatiety of alligators, crocoliles, and caymans shows that they have evolved from the ancient fossil forms. There have been no pressure to change the basic body morphology.

If a subpopulation were to evolve to be more land based, it might develop longer legs and a shorter tail (since it won't use it for swimming). At some point, you would classify it as a different creature because its body morphology was suitably different.

Humans have less genes than frogs. Frogs have variants of some genes that are optimized for different temperatures. Thermoregulation has benefits, especially when humans just need to add or remove clothing.

Answer 7

You're quite right---well-adapted species may not evolve much, because they're not under much pressure from natural selection.

It would be unlikely that humans would become more like gators, because we don't live in the same ecological niche as they. Future humans are more likely to evolve traits that directly enhance human survival, for example resistance to AIDS or cancer.

One easily-pedictable change is humans is development of darker skin---now that we understand how to make synthetic vitamin D, light-coloured skin is no longer an advantage, whereas dark-coloured skin is a big advantage in hot sunshine.

Answer 8

It can be explained bu natural selection.
The gators stopped evolving because they didnt had to evolve.
YOu have to know that gator evolved too. It just stopped becuase there was no need to evolve anymore.

And species cant evolve instantly it takes hundreds, thousands of years to evolve. Instant change of environment will make species extinct.

It is very hard to answer the last question, becuase it is very complicated problem. It involves future technology, climate, environment etc... But I'm sure the basic overall geometry of human wont change.

Answer 9

Alligators and crocodiles have evolved in the past 65 million years. Trust me...you wouldn't want to old types of crocodiles around (very big...very powerful..and luckily, very dead.) Same for the Great White Shark, that thing hasn't really changed all that much for a few million years...maybe more, because it's the perfect killing machine. I have no clue on how humans will evolve...I'm not a fortune-teller..or Nostradamus...but, I would think that, if we do continue on for a few more million years, that our brain size would increase, and our physical bodies might either decrease in potency or increase depending on the lifestyle that a majority of us have...anyway...hope this helps some...

Answer 10

Sign..... Gators have evolved over the years, they have become more efficient, we know this, but why haven't they radically changed? Gators don't, and haven't had for sometime, any natural predators in their habitat. They are the top of the food chain, they don't need to change in order to survive.'

Humans, or most of them anyway, are not bound by nature anymore, so we have nullified the driving force of natural selection, nature. We will still change through the other mechanisms such as sexual selection, but unless a global catastrophe happens and we are forced into survival mode, the changes will be suddle.