What is the concept of evolution?

Question

I mean, look at it this way, sperm and an egg meet, they are not human. They become a bunch of cells that "Evolve" into a human. Wouldn't that be the concept of evolution? If this happens in 9 months, who's to say that in a million years one species didn't evolve into something else?

Answer 1

It's more like this. I'll illustrate with a nice, easy organism, the bacterium. Say I have some bacteria. E.coli, for instance, since I've worked with them before. Say these E.coli tend to die when I treat them with ampicillin. Now, I add a plasmid (a piece or circular DNA) to the bacteria. This plasmid contains a gene for a protein that protects the bacteria against ampicillin. Now, when I add the ampicillin, the bacteria with the plasmid are much more likely to survive than the bacteria without it.

That's an extreme case, but it illustrates the point. (However, in this case, since I didn't want to wait for a helpful mutation--mutations happen naturally, but I want my lab work to happen overnight--I made the change in the DNA myself.) The strain with the favorable genes was more likely to reproduce, in this case because they survived.

Helpful mutations can be predictable, as recent experiments by Yousif Shamoo (my advisor while I was an undergrad) have shown, since in some cases, certain mutations are much more favorable than most. Often, though, it's just a matter of mutations happening that tend to help. Most don't, so they don't spread. Many mutations, especially to important genes (such as Hox genes) can have effects much more dramatic and macroscopic than simple antibiotic resistance.

You don't need environmental selection that wipes out a population to work. Instead, you can simply have something that favors reproduction in one variation slightly. You can run a computer simulation of this, and in the long run, the more favored version will win out. That doesn't mean the other strain necessarily goes away. It might mean that birds with pretty feathers are better at attracting mates, for instance.

It all makes sense when you have some idea of what's going on.

Answer 2

Ergh... that's not quite what evolution is about.

The idea of evolution is that if a certain genetic trait helps with reproduction, then that trait is passed on more easily to the next generation. Over time more and more of a species possess that trait. "Helping with reproduction" also includes any traits that aid in the survival of an organism so that they can produce more offspring.

As a side note, usually people call whatever aspects of the world that make certain traits beneficial to have "selective pressures," that is where the term Natural Selection comes from. Also, this is why we will never evolve a resistance to most types of cancer, because usually kill off people only AFTER they've reproduced and Natural Selection cannot act on it.

Mutations of traits happen at random throughout any species population and that is how new species form. After enough such beneficial mutations are successfully passed on that the new version of the species is significantly different from the old one to the point where the new version cannot breed with the old one, we say that it has evolved into something else.

Evolution has to do with differences between generations. Organisms don't evolve by themselves, what you are talking about with your human birth example is a method of reproduction, not evolution.

Answer 3

You are leaving out a basic truth here. The sperm and the egg are both created by a human. So they grow into a human. That is reproduction, not evolution.

Evolution is a species making changes within itself in order to adapt to its environment. All species do it all the time. And new species are created this way. Of course it takes a long time to see those results. On evolutionary change going on in the human species right now is the lack of wisdom teeth. I have 3 children. 1 has his wisdom teeth. The other 2 don't. The doctor told me this is a change that has been occurring among humans for the last 30 years or so. Small change but significant.

Answer 4

A bunch of cells don't evolve into a human. Evolution is changing into something new and then that changes into something new again, isn't it? People don't change into different types of human in the womb. They grow don't they?

Evolution is something changing slowly over time to something new. Hypotheical - a lizard changes to a bird (like some scienists believe happend). Somewhere along the line you would get a half-bird half-lizard, right? Two big problems with that. Firstly, shouldn't there be millions of these fossils if it takes millons of years to evolve. Surely these creatures died. Secondly, wouldn't a creature with a half-grown wing be at a huge disadvantage in the food-chain scale of things. It can't fly with half a wing, predators would help themselves to an easy meal. That would make it very hard to for that species to not become extinct.

Answer 5

That is not, at all, the way evolution works. It is a very slow process that takes millions of years (usually). It works sort of like this. A thing is born with a small mutation ... say a longer beak in a bird. It may turn out that this longer beak makes it easier for this bird to get food and thus it is more likely to survive to produce offspring than the birds with the shorter beak. Its children may have longer beaks as well and they in turn will be more likely to have offspring. After time all of the birds of this type may have longer beaks ... or perhaps just the birds of this type in a certian area. Over time, as enough of these "changes" build up you can end up with entirely new species.

Answer 6

Growth, and evolution, is not the same thing.

A plant growing from seed to flower is not evolving. A zygote growing into an adult is not either. Evolution happens at the genetic level, from variation in mutation from generation to generation, with the more fit (or sometimes moore lucky) being more numerous in the world, and the less fit or less lucky, less numerous.

Answer 7

Evolutions basic concept is that it's process driven...There are processes at work changing us and everything else...Examples are survival of the fittest/natural selection. Another example is that it's estimated that in 10K years we won't have our little toes anymore as they don't serve any useful purpose in terms of balance or walking. This is being studied through the fossil record and the little toe has been getting smaller and smaller over time and will cease to exist eventually. PEACE!

Answer 8

conception is what you call when and egg cell and sperm cell meet, evolution is when a single cell organism develop and become a multi-cell unit which evolve furher into a more complex organism. e.g. from a plankton to a seeweed, or a macaque to an orangutan. one best sample is, children tends to be more taller and smarter than their parents.

Answer 9

Well, your example isn't really correct.

Evolve - change or adapt.

Develop - to bring into being gradually.

A sperm and egg come together to develop into a baby. Not evolve.

Answer 10

no, thats not evolution.

basically, evolution says that animals change over time. changes that have an advantage become more widespread, changes that do not have an advantage die out.
over a long time (millions of years) these changes become very different and new species come about.