natural selection??? (Evolution)?

Question

Ok, how does the environment play a role in Natural selection, and in turn evolution. My teacher explained this, but I didn't understand it very well, and have a test over the subject tomorrow. Can someone please help me????

Answer 1

The environment, in the evolutionary model, is what is doing the selecting. Creatures which do well in an environment will be healthier and live longer than creatures which do poorly. And different environments require different characteristics in order to do well.

It bears mention that the 'environment' in the evolutionary sense is not necessarily as large as when the term is used in other senses. It is more analogous to the biological term 'niche', if you're familiar with that one. In lay terms, it is just pretty much everything a creature interacts with and not much else.

So to pick an example, a tapeworm's environment is the inside of a creature, and wherever its eggs go in the process of getting from one creature to another. A cow's envioronment, on the other hand, is going to include meadows, predators, and even people and tapeworms. If either of them get a mutation that helps them in those environments, their offspring will be favored. Like a tapeworm that can shoot itself directly into new cows, or a cow that cannot be affected by tapeworms. If they get a mutation that, say, makes them immune to HIV, then it will be meaningless, since HIV doesn't affect them anyway (it's not a significant part of their environment).

Hope that helps!

Answer 2

The environment is the stage on which evolution is played. Some parts of the environment help, and some parts harm, the organisms living therein. The environment IS the nature in natural selection.

Take, for example, a cold snap. It kills most of the adult mosquitoes that happen to be around. Some survive because they were lucky enough to be in a warm spot under a tree. Others survive because they bear alleles that make proteins that provide some resistance to cold. The next generation of mosquitoes will have slightly more of the cold-resistance alleles than the previous. The population has evolved towards greater cold resistance.

Answer 3

Think of the "deep thermal vents" in the mid-Atlantic Ridge. These are vents in the ocean floor where water up to 250 degrees hot come out and lots of things live in it! HOW? By adapting to the hot water and changing color to survive at such great depths, it is "the deep" thermal vents. So, almost everything down there will be white. This is to save energy on color, and there is no use for a protective layer against the sun and the fact that the heat would remove most. So, these animals would need to adapt to the blackness of the deep. It would need to find a way to live on some source of energy that wasn't driven by the sun, such as normal plants do. Chemically, instead, is how, by absorbing the minerals that come up out of the earth thru the vents, the plants/animals absorb and grow. So the basis of life is chemically based because there is no sun to grow the plants.

You also have vents every so often on a ridge, so there are little "islands" of life along a ridge top, each one just a little different from the last, growing its own unique environment. All the plants located around a hot water vent, everything white and absorbing minerals for food instead of sunlight.

Answer 4

The environment presents challenges to the variable organism ( we will stick with organism centered selection ) Say an environment is getting colder. The organisms who are incrementally longer coated will out compete organisms in their species who are not. They pass on the genes for this advantage and incrementally, as the assortive mating of this species takes place, the coats get longer to meet the environmental challenge. Evolution is this way, " adding up the small advantages and subtracting the disadvantages, all the time and every where ".

Answer 5

Think about it this way in this...scenario, I guess you can call it. Once global warming melts all the icecaps and floods the planet, some species will adapt to living with so much water, and physically evolve to do so (like humans developing gills to breathe underwater, let's say). Hope this helps.

Another phrase for natural selection is "survival for the fittest." Whoever's stronger will survive, whoever can evade predators will survive. All other species who are..."lazy," for a lack of a better word, will become extinct after being eaten or not eating.

Answer 6

Evolution does not call for something. Evolution is only substitute in genetic makeup and gene frequencies via the years. this would be a help in gene type, an advance in gene type, or a transformation interior the share of genes in one inhabitants whilst in comparison with a distinctive, between different issues. organic determination is a single agent of evolution. it somewhat is the main significant agent, and oftentimes what we expect of of as quickly as we expect of approximately evolution, regardless of the undeniable fact that it is not the only evolutionary rigidity at paintings. Others comprise gene bypass, genetic drift, sexual determination, synthetic determination, and mutation. organic determination does certainly paintings to shrink version. In a inhabitants with fairly a lot of variety, those persons that are the ultimate adapted to their particular ecosystem would be chosen for, and those least adapted would be weeded out. bear in techniques, nonetheless, that the fairly some different evolutionary forces actively advance version on an identical time. New mutations and sexual reproduction the two generate version. Gene bypass (flow of genes between populations) may additionally produce extra suitable version. in case you have 2 very distinctive populations that come to interbreed, version will bypass up as foreign places genes are presented into each and each inhabitants from the different. lower back, evolution has no standards. it somewhat is only a attitude of substitute. it is the guy forces of evolution which could the two paintings in unison or paintings in opposition to produce categories of substitute. Evolution as an entire is powerless through fact it somewhat is only the term for a technique.

Answer 7

More to the point, lifetime reproductive fitness is the ONLY thing that matters. Those individuals with the characteristics that will allow them to have the largest number of viable offspring in a given environment will be selected.