However, it is curious that most mammals such as dogs and horses die much younger than we do, despite being made of essentially the same stuff. Certainly we could not exist if we died under twenty years because it takes us that long to mature our minds and breed. But what advantage for a dog to die young? If it lived twice as long it would (presumably) produce twice as many grandchildren.
I suspect that it is simply that dogs and horses can breed after a couple of years. So once they live more than 6 or so times their breeding age their is not that much advantage in them living any longer. But there would still be some advantage. Is there some cost to living longer, such as needing to have a slower metabolism, or is it just that natural selection does not produce unneeded features?
I think that you are right and Lander is wrong.
However, it is curious that most mammals such as dogs and horses die much younger than we do, despite being made of essentially the same stuff. Certainly we could not exist if we died under twenty years because it takes us that long to mature our minds and breed. But what advantage for a dog to die young? If it lived twice as long it would (presumably) produce twice as many grandchildren.
I suspect that it is simply that dogs and horses can breed after a couple of years. So once they live more than 6 or so times their breeding age their is not that much advantage in them living any longer. But there would still be some advantage. Is there some cost to living longer, such as needing to have a slower metabolism, or is it just that natural selection does not produce unneeded features?