If Evolution is the only logical choice (not a belief system), why don't Dophins and whales not have gills

Question

Also, what about homosexuality, Clearly, nature has no purpose for any group of beings that can not reproduce.

Looking at some of the answers I see, I find it amusing how some of you automatically take a hostile tone. If you don't like the fact that someone is asking an honest question, or you need to make assumptions about the asker, rather than evaluating the question, and making an attempt at giving an answer worth reading, maybe you should skip the question and move along until you find something that fits your mindset. NONE of you have ever met me, so you don't know anything about me, with the exception of what is posted on my profile, and my questions. With that in mind, you could probably provide more insight by answering the question than you could by analyzing the asker.

Answer 1

Because they're mammals.

And why do you say that nature has no purpose for any group of beings that can not reproduce? Clearly, you have read some pamphlets on Creationism and think you're an expert.

Nature has lots of purposes for beings that don't reproduce. Look at a bee colony for one example...

Answer 2

Dolphins and whales do not have gills because they are mammals. Their evolutionary history is a bit convoluted. All life started out in the sea, but at some point, some populations began to spent some, and eventually all of their time on land. Obviously, mammals evolved from that early population of land animals. Then marine mammals like dolphins and whales when BACK into the water. But they were constrained by their evolutionary lineage, so they're stuck with mammalian lungs rather than gills.

Believe it or not, homosexuality actually can be considered adaptive under some circumstance. A given ecosystem can only sustain so many individuals of a species, so the population can only grow so much before individuals start dying of starvation or lack of other resources. But because humans derive pleasure from sex, our biological instict is basically to do it as often as possible. So having homosexual relations allows individuals to get their sexual pleasure without wasting energy making a baby that's just going to die anyway (I know that sounds harsh, but evolutionarily the only downside to having a baby die is that it's a waste of energy to make a kid that doesn't survive to reproduce). Of course, that doesn't explain why people would be exclusively homosexual, but the factors that influence a person to be homosexual are not well enough understood to comment on it with any degree of certainty. It is likely that there are some environmental factors invovled, which would have no bearing on evolution.

Answer 3

The reason dolphins and whales have not evolved to form gills is that that evolution doesn't create with a purpose. You are supposing that evolution has to have a reason to do something when in reality, it does not.

Dolphins and whales currently do fine without gills... there is no reason for them to have developed them. On the other hand, evolution and natural selection will continue to favor dolphins and whales that are more adapted to their aquatic environment with each successive generation. That means if a dolphin is born that can hold it's breath 3 times longer than other dolphins can, it is more likely to survive to pass on its genes.

As far as homosexuality is concerned. You THINK that nature has no purpose but with what divine logic are you using? If you believe in God, why did God 'invent' homosexuality if its unnatural?

But if you want an explanation when there doesn't need to be one, here's one:

A recent study indicated that a woman is more likely to have a child grow up to be homosexual if she is under stress during her pregnancy. It makes logical sense in biology to inhibit the reproduction of the species if the species is under a certain amount of stress because pregnancy and child rearing takes a lot of time and resources. If a community is under stress, it's obvious that conditions are not favorable to have more children.

While you would think that nature would want a species to be more fertile, this does not make sense in mammals because of our long gestation periods and long child rearing times. If a mother and father under extreme environmental stress, such as drought or famine, having more children is more likely to cause more deaths.

In this case, resulting children becoming homosexual becomes an control to population when resources are low.

And finally, once again, nature does not need to have a purpose for everything it does. When it comes to reproduction, the biotic potential is typically so very high than even an inhibitory factor such as homosexuality is easily overcome. And simply because you cannot see a purpose for it, doesn't mean there isn't one.

Answer 4

First, the reason people's answers are so hostile is that your question appears hostile. It starts out with the accusation that Evolution is nothing but a "belief system", and continues on that a certain group of human beings have "no purpose".

However, on the assumption that you are asking a genuine question because you sincerely want to know the answer ... I'll offer a less hostile answer.

Dolphins and whales don't have gills because they evolved from land animals. They are mammals, and the mammal branch originated on land. If you look at the skeletons of dolphins and whales, they have vestigial hip bones and leg bones that are evidence of a once-terrestrial past. (There is also a lot of fossil evidence, genetic evidence, molecular evidence, embryological evidence and more morphological evidence of descent from land animals, but let's move on.)

They haven't re-evolved gills (which mammals originally lost, as evidenced by gill slits in the embryos of all mammals, including humans), for a simple reason. They are doing just fine without them. Yes, they might do even better with gills, but nature doesn't work that way. Just because some adaptation A would have some advantage, doesn't mean the organism *has* to evolve it. An intelligent designer would deliberately equip an organism for its environment ... evolution is the result of millions of random accidents, filtered by nature's selection of those that happen to work best.

In fact, the lack of gills on dolphins and whales which would be useful, and the presence of hip- and leg-bones, which are useless, are all evidence *against* intelligent design ... which is why ID is *not* a logical choice.

So that is why there is (currently) no other logical choice on the table but evolution.

...

As for homosexuality, that is more complicated because we do not yet know how much is genetics and how much are environmental factors. Natural selection only operates on a characteristic to the extent that it is *heritable*.

Nevertheless, the evidence is growing that homosexuality is at least partially genetics. It would seem that a gene that reduces its own tendencies for reproduction would not do well in natural selection. But as long as it is *recessive* then a gene can exist quite well in a population.

But the real answer is that this is a normal part of variation. We tend to group things in binary (yes or no) categories ... you're either gay or straight, left- or right-handed, tall or short. But it's really on a spectrum. You can say that there are tall people and short people, but in reality there is a variation from very short to very tall, with most people in the middle. People think that everyone is either left- or right-handed, but in reality there's a spectrum (I am extremely right-handed, my brother is primarily left-handed, but fairly ambidextrous ... he throws with his left hand, but writes and draws with his right.)

The same applies to homosexuality ... there aren't just two categories 'gay' or 'straight' ... there is a variation in a spectrum. The majority of people are born with the genetics to be predominantly 'straight' (just as most people are born with the genetics to be predominantly right-handed). Then add to that the extreme social pressures to suppress the expression of any of the genetics to be predominantly 'gay', and only people in which this is very predominant will get through the social filters and identify themselves as gay. (I personally believe that the pain this causes people is *criminal* ... but the people who suffer most are those near the border, who have some 'gay' predispositions, but suppress them violently ... these are usually the people who are the most homophobic, hateful, and at times violent towards homosexuals ... if you're truly comfortable with your own heterosexuality, there is no reason at all to feel threatened or hateful towards homosexuals.)

So homosexuality is a perfectly normal part of the *spectrum* of variation in sexual preferences. Variation isn't just consistent with natural selection ... it is an integral part of it.

I hope that answers your questions.

Answer 5

Dolphins and Whales are mammals not fish.

They are assembled mechanically from spare tuna parts at Sea World-Busch Gardens. They ran out of spare gills and gave them blow-holes instead.


Gays can reproduce. Although they need the participation of the opposite sex to do so.

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Answer 6

The cetaceans have lungs and clearly descended from terrestrial animals. Maybe in several million years they will evolve something like gills. The blowhole is the nostrils migrated to the top of the head. Internally, it has nasal structures associated with it.

Answer 7

What's your point?

Why should dolphins and whales have gills? They seem to do OK. Perhaps nature does have a purpose for homosexuality. Who knows? Who are we to say?

Answer 8

I don't believe that the evolution would be one day the logical choice as some people think that the nature created us..Also the homosexuality is a psicological dieseas

Answer 9

as for homosexuality, there is a logical reason for this.
the world is overpopulated.
it is an adaptation to be homosexual. it's nature's form of birth control.

Answer 10

Shortly Dolphin will also start to speak. Then they will reply.