Why have some of the steps in our evolution been retrograde?

Question

Take the digestive system first it it was a two way process then an anus developed and it was one way trafic only. With resparation fish have it one way only but we excrete breath the same way it came in. Not very effective

Answer 1

Descent with modification. We have several vestigal organs such as the appendix, muscles to move our ears, left over membrane in our eyes, etc.

Pollution in the air is forcing our lungs to evolve. Of course, this evolution won't be seen in our lifetime.

Answer 2

Evolution is the development of different adaptations that lead one part of species to greater success than another. One-way digestion has evolved twice independently in both vertebrates and invertebrates. A one-way digestive system is far more effective, especially for terristrial vertebrates that need to reabsorb water from their fecal matter).

As a matter of fact, our method of breathing is quite effective or we wouldn't be alive, would we? Terrestrial vertebrates evolved from dipnoan fishes that breathed air and had only rudiments of gills because they were no longer functional. Organisms, in the long haul, do not invest energy in developing structures (like gills) that have no advantage. Therefore, as these fish relied increasingly on breathing air, the ones that invested less energy into developing gill slits would have a larger reproductive advantage (be able to make more babies like them) than those with many nonfunctional gills.

Before you take a stand on an issue like this you really need to know the ACTUAL science behind it, not just what you think it stands for. Pick up a book!

Answer 3

Strongest survive. When we have something that works we keep it. It it doesn't work more than likely that trait will be lost do to us not surviving and passing it on to our offspring. evolution is also a very slow process.

Fish breathe the way they do since it is the most efficient process from them. Our breathing works good for us.

Answer 4

Its Murphy's Law.
known as 1 step forward 2 back.

Answer 5

no steps of evolution are retrograde - nothing evolves backwards.
evolution is an adaptive process dependent on individuals with characteristics that enhance their survival and the survival of their offspring.

Answer 6

Clearly you don't know how to play the didgeridoo. I don't either. Though you have a valid point: beginners would find the didge easier to play with their anuses.

Answer 7

That's simple, evolution is a crackpot theory !

Answer 8

evolution is adapting to fit the enviroment. not upgrading.
if a feature becomes redundant we lose it.

Answer 9

evolution is what needs to happen in your brain, start using your other brain cells

Answer 10

hey if your looking for an upgrade go to Microsoft