Evolution by Natural Selection

[Alan Grayson]

Lately, I've watching videos about the animal kingdom, and I am beginning to question Darwin's claim of evolution by natural selection. I wonder; how does this explain the appearance of defensive horns on some animals, like the Rhinoceros, and not on others, such as the Zebra? AG 

, and not on others, such as zebras? AG

[Alan Grayson]

On Thursday, December 4, 2025 at 8:21:03 AM UTC-7 Alan Grayson wrote:

Lately, I've watching videos about the animal kingdom, and I am beginning to question Darwin's claim of evolution by natural selection. I wonder; how does this explain the appearance of defensive horns on some animals, like the Rhinoceros, and not on others, such as the Zebra? AG 

Does Natural Selection mean that random changes in an animal's body, such as a very small horn on a Rhonoceros initially, gives it some minor competitive advantage, and that horn grows bigger over time, again randomly, until it gets large as we see today? And yet on other specie of plant eaters, like Zebra, no such process occurred?  The process IMO looks teleological, that is, intentional in relation to interactions with the environment, not random. AG

[Alan Grayson]

On Saturday, December 6, 2025 at 5:34:48 PM UTC-7 Alan Grayson wrote:

On Thursday, December 4, 2025 at 8:21:03 AM UTC-7 Alan Grayson wrote:

Lately, I've watching videos about the animal kingdom, and I am beginning to question Darwin's claim of evolution by natural selection. I wonder; how does this explain the appearance of defensive horns on some animals, like the Rhinoceros, and not on others, such as the Zebra? AG 

Does Natural Selection mean that random changes in an animal's body, such as a very small horn on a RhInoceros initially, gives it some minor competitive advantage, and that horn grows bigger over time, again randomly, until it gets large as we see today? And yet on other specie of plant eaters, like Zebra, no such process occurred?  The process IMO looks teleological, that is, intentional in relation to interactions with the environment, not random. AG

That is, it seems like a Rhinoceros developed a horn (actually two horns), because it needed it, whereas Zebras never developed horns because they ddin't need them. AG 

[John Clark]

On Sat, Dec 6, 2025 at 7:34 PM Alan Grayson <agrays...@gmail.com> wrote:

> Lately, I've watching videos about the animal kingdom, and I am beginning to question Darwin's claim of evolution by natural selection. I wonder; how does this explain the appearance of defensive horns on some animals, like the Rhinoceros, and not on others, such as the Zebra? Does Natural Selection mean that random changes in an animal's body, such as a very small horn on a Rhonoceros initially, gives it some minor competitive advantage, and that horn grows bigger over time, again randomly, until it gets large as we see today?

If a rhino has a gene for producing a slightly larger horn and that gives it a small competitive advantage, either by becoming a better fighter or because female rhinos think big horns are sexy (sexual selection is the reason male peacocks have such ridiculously large tail feathers) then that gene is more likely to enter the next generation. The reason the horn on a rhino is not even larger is because Evolution doesn't have infinite resources at its disposal, so if you do more of one thing then you must do less of some other thing, and that other thing may have more survival value that a larger horn.

 

> And yet on other specie of plant eaters, like Zebra, no such process occurred? 

Natural Selection can only select from among the genes that are available, apparently in horse-like animals such as zebras random mutation never produced a proto horn gene, and that's why Evolution never produced a unicorn, although if random chance had been slightly different it would have. However the ancestors of zebras did have a gene, produced by random mutation, that no rino had, that caused a slight variation in the color of its fur, and that gave a zebra a slight advantage because it turns out that disease carrying tsetse flies and horseflies have trouble landing on striped surfaces because the stripes interferes with the flies visual systems causing them to abort landing on them.

If you're really interested in this sort of thing you should read (or listen to on Audible) Richard Dawkins wonderful book "The Selfish Gene", it's one of the 3 or 4 best books I've ever read in my life, and I read a lot.  

John K Clark    See what's on my new list at  Extropolis

ax9

[Brent Meeker]

On 12/7/2025 6:13 AM, John Clark wrote:

On Sat, Dec 6, 2025 at 7:34 PM Alan Grayson <agrays...@gmail.com> wrote:

> Lately, I've watching videos about the animal kingdom, and I am beginning to question Darwin's claim of evolution by natural selection. I wonder; how does this explain the appearance of defensive horns on some animals, like the Rhinoceros, and not on others, such as the Zebra? Does Natural Selection mean that random changes in an animal's body, such as a very small horn on a Rhonoceros initially, gives it some minor competitive advantage, and that horn grows bigger over time, again randomly, until it gets large as we see today?

If a rhino has a gene for producing a slightly larger horn and that gives it a small competitive advantage, either by becoming a better fighter or because female rhinos think big horns are sexy (sexual selection is the reason male peacocks have such ridiculously large tail feathers) then that gene is more likely to enter the next generation. The reason the horn on a rhino is not even larger is because Evolution doesn't have infinite resources at its disposal, so if you do more of one thing then you must do less of some other thing, and that other thing may have more survival value that a larger horn.

 

> And yet on other specie of plant eaters, like Zebra, no such process occurred? 

Natural Selection can only select from among the genes that are available

That's a little misleading since the genes that are available include new random mutations.

, apparently in horse-like animals such as zebras random mutation never produced a proto horn gene, and that's why Evolution never produced a unicorn, although if random chance had been slightly different it would have. 

Ironically, nature did produce a unicorn.  It's the rhinoceros, which Pliny the Elder described in his book "Natural History" which latter fed into legends of a unicorn.

However the ancestors of zebras did have a gene, produced by random mutation, that no rino had, that caused a slight variation in the color of its fur, and that gave a zebra a slight advantage because it turns out that disease carrying tsetse flies and horseflies have trouble landing on striped surfaces because the stripes interferes with the flies visual systems causing them to abort landing on them.

If you're really interested in this sort of thing you should read (or listen to on Audible) Richard Dawkins wonderful book "The Selfish Gene", it's one of the 3 or 4 best books I've ever read in my life, and I read a lot.  

I second that recommendation.

Brent

John K Clark    See what's on my new list at  Extropolis

ax9

--
You received this message because you are subscribed to the Google Groups "Everything List" group.
To unsubscribe from this group and stop receiving emails from it, send an email to everything-li...@googlegroups.com.
To view this discussion visit https://groups.google.com/d/msgid/everything-list/CAJPayv33gRmBe%3DU9ZJsgHWcfCjj4Zx%2B1UdEctLCkB6SGMAwdTg%40mail.gmail.com.