delboy

The book Evolution by Futuyma deals with a lot of the maths of evolution, but it's pretty advanced. Maybe I should say very advanced actually.

1. Evolution doesn't work in straight line graphs 2. Yes. If we don't go extinct we will become a new species. If the second species is plural - that seems unlikely as genetic isolation of 2 populations seems improbable. 3. Something extinct cannot evolve again - extinction is final. Something similar - seems unlikely but who knows.

An evolutionary biologist would no doubt know how to extract the relevant information to construct a tree. As CharonY said, certain genes indicate the species relationship more reliably, so use those ones. Phylogenetic trees are not constructed to prove evolution. Scientists simply accept its truth (unless and until it may be happened to be proven wrong). If you wish to use them as evidence you simply have to quote CharonY's extra detail - which actually contains information, unlike the video, which simply states (false) things without providing any evidence.

A goal is something in the future to strive towards. If we're using that definition of goal, then it can never be applied to evolution. A strong drive to reproduce is something that will be selected for and therefore evolution will bring it into being. But there was never any goal to end up this way, it just happened due to the chance happening of mutations and their subsequent selection. So it's more accurate to say that the drive to reproduce is a product of evolution, not a goal.

If you talk about goals in evolution you're putting the cart before the horse. It's like saying that if you throw a stone off a cliff it's goal is to reach the ground . If there is a goal, it is for an individual to pass on its genes. Any evolution that takes place is simply an 'unintended' consequence. And you're picking on some very convenient examples to support your idea. You'd need to research a genuinely inclusive sample of all life forms to support your claim. You ought to look at all living things in producing this sample, and if biomass is a measure of success then plants are by far and away the most successful group: https://www.pnas.org/content/115/25/6506 And they seem to do pretty well without brains.

You haven't defined how far you want to go back in asking what they evolved from. The answer would be very different depending on this. I am assuming you are after another species of ape. In any case these things are impossible to define. Because the evolutionary tree is always constantly branching, and fossil records are very patchy, it can never be said for sure if something is a true ancestor or just a 'cousin'. And as far as I know there are no (or very few) fossils of recent ancestors of gorillas. Every living thing shares an ancestor with humans including bacteria. Again, it just depends how far you go back. The most recent common ancestor is what you're after and our most recent ancestor with gorillas existed around 7 million years ago (cf Chimp - 6 million, orang utan - 14 million)

Of course, I stand corrected.

The picture you post begins to answer the question. All those muscles evolved and they're all vital. Plus every other part of the human body. Why try and reduce a question with the most complex answer to a single sentence? The human body is evolved to do everything you'll read in a human biology textbook. A better question might be to ask how we are different from, for example, the last common ancestor we share with chimps which existed about 6 million years ago. Which Mistermack's post addresses. And you'll get a different answer according to what species you choose to compare us against. For example you'd say we are evolved to have large brains to make advanced tools if you compare us with apes, but you'd say we are evolved to walk on land if you compare us with our fish ancestors.

They certainly benefit themselves. Which is what ALL species do, nothing more. And by doing that they contribute to an ecosystem and they evolve. Defining benefit to an ecosystem or evolution is really just adding a human emotion to the question. Our intellect/emotions seem to define that a vibrant ecosystem or active evolution is somehow a good thing. But this is just a perception, and everyone will have a slightly different view anyway. It's a bit like the common question I hear - "What's the point of wasps?" My answer is that the point of a wasp is to be a wasp. What's the point of a human to a wasp? Not much. Everything that's living is part of the ecosystem, whether you consider it a 'parasite' or not. It will eat something else, and when it dies it will pass on the organic compounds to other living things. Just like humans. I guess we're all parasites if you stretch the definition. But if you want to see it as benefit, then everything that exists 'benefits' the ecosystem because it is part of it. Similar with evolution. A parasite might cause the host to evolve mechanisms to resist it. You might see that as benefit. Or it might just be happenstance. But I think I would certainly say parasites are certainly not counterproductive. They benefit themselves, which is what we all do. They might be counterproductive to the host, but lots of things eat other things and we don't define them as parasites because they don't happen to live on a host.

'Evolution' by Futuyma and Kirkpatrick seems like a standard text book to me.

OK, if they're closely related it could work. While on the subject of populations with alpha males, there always seems to be plenty of non-alpha/smaller males around, so I'm sure there's plenty of sneaky matings going on. EDIT - as mistermack has already said. Females will be happy to choose sneaky males if it leads to reproductive success in her male offspring. Some cuttlefish males imitate females to fool a male and sneak in with his female.

But it would have an evolutionary advantage to a different individual, so the homosexual genes, if that's what they are, would be selected against and reduce in the population.

Lets say life began 3.5 billion years ago. Now lets imagine every million years each species divides into 2 species. Now lets assume that extinctions don't happen - I know that's false but assume for the sake of this argument. So the number of species doubles every million years. I make it that after just 30 million years there would be around half a billion species. So after 3500 million years??? I don't think my calculator can handle that. So obviously extinctions also have to be taken into account. But my point is that given the time span, the creation of a few million species is no problem at all. This argument only considers species numbers, but the argument for diversity of form is much the same - over such a vast amount of time there is ample scope for such variety to evolve.

That's perfectly possible. Evolution (natural selection) only happens at the level of the individual (or even the gene it can be argued). Individuals will do what they can to pass on their genes, even if this is to the detriment of the species as a whole. Many many species have become extinct because of such reasons. I think some believe evolution can happen at species level but I don't think there's any convincing evidence.

I believe the spelling is 'gneiss'