Will last 2 Wolly-rhinos (siblings) in US mate?

  • Thread starter Thread starter jackmell
  • Start date Start date
Click For Summary

Discussion Overview

The discussion centers around the mating prospects of the last two woolly rhinos in the U.S., who are siblings. Participants explore the implications of sibling mating from evolutionary, genetic, and behavioral perspectives, questioning whether instinctual or social factors influence their ability to mate.

Discussion Character

  • Debate/contested
  • Exploratory
  • Technical explanation

Main Points Raised

  • Some participants suggest that there may be an instinctual taboo preventing siblings from mating, arguing that selective pressures in their genotypes would hinder such behavior.
  • Others counter that there is no inherent mechanism preventing sibling breeding, and inbreeding can serve to eliminate bad genes from a population.
  • One participant raises concerns about inbreeding increasing the likelihood of recessive genetic disorders, proposing that natural selection would favor non-related partners over related ones.
  • Another participant proposes an observational study comparing the mating behaviors of unrelated rhinos versus siblings to assess any differences.
  • Some express uncertainty about the frequency of inbreeding in the wild, suggesting that natural selection may eliminate less fit offspring before they reproduce.
  • A later reply emphasizes that in the case of the two woolly rhinos, inbreeding may be preferable to extinction, while questioning why inbreeding is less common in larger populations.
  • One participant notes that social learning rather than instinct may play a significant role in preventing close breeding among mammals.
  • Another participant mistakenly references woolly rhinos, later correcting to Sumatran rhinos, and discusses the unnatural conditions of zoo mating.

Areas of Agreement / Disagreement

Participants express a range of views on the topic, with no clear consensus reached. Disagreement exists regarding the role of instinct versus social learning in mating behaviors, as well as the implications of inbreeding in both captive and wild populations.

Contextual Notes

Limitations include the reliance on anecdotal evidence and assumptions about animal behavior, as well as the potential for differing definitions of inbreeding and mating behaviors across species.

Who May Find This Useful

Readers interested in evolutionary biology, animal behavior, genetics, and conservation efforts may find this discussion relevant.

jackmell
Messages
1,806
Reaction score
54
Apparently wolly rhinos are on the brink of extinction and there are only two left in America, a brother and sister, that what, zoologist are trying to get to mate. Isn't there some instinctual taboo the siblings will detect preventing them from mating? Surely this can be argued on Darwinian grounds right?

I just cannot see how selective pressures layered down in their genotypes would allow them to mate easily, or "naturally" I mean.

Or is it common for (mammalian) siblings to mate in Nature?
 
Biology news on Phys.org
No and no and yes.

There is nothing that prevents sibling breeding. It is a very good way of removing bad genes from a population.
 
I thought the opposite was true. Inbreeding increases the chance for bad recessive genes to show. I could definitely see how natural selection would dictate a sort "taboo" against it.

I know, Wikipedia isn't a great source but check this link out.

http://en.wikipedia.org/wiki/Inbreeding
 
In the Wikipedia article about inbreeding at least as it relates to lion prides:

"There is no mechanism for preventing inbreeding or to ensure outcrossing"

And I guess I'm surprised to see that. If inbreeding is an undesirable trait, then isn't Natural Selection deselecting (reducing their frequency) this practice of breeding? Surely in the wild, non-related potential sexual partners are seen as more fit than related partners since I assume non-related sexual selection in Nature dominates over related paring. If that's true as I believe it is, then there must be some selective force at work in the female selection process choosing appropriate non-related mates over related ones.

I'm not sure about this however so I wish to run a test: observe two sets of wolly-rhinos: The first set, completely unrelated, bring them (male and female) together and observe their behavior. Second set: brother and sister likewise.

Am I to believe I will not observe any difference in behavior between the sets?
 
Last edited:
It does seem odd(at least to a math major, rather than a biologist), given the negative effect of inbreeding on a gene pool, that animals have no predisposition against inbreeding, and yet to my (limited)knowledge it does not happen often.

Is it possible that inbreeding does occur more often that we are assuming, only Natural Selection weeds out these less fit offspring before they are allowed to reproduce?

Any experts out there?

Definitely an interesting question. I hope someone can shed some more light on this.
 
Last edited:
jackmell said:
The first set, completely unrelated, bring them (male and female) together and observe their behavior. Second set: brother and sister likewise.

Am I to believe I will not observe any difference in behavior between the sets?

You aren't thinking this through properly.

If there the second set don't inbreed, they are guaranteed to go extinct in one generation.

If they do inbreed, they may or may not go extinct.

So which option does natural selection favor?
 
AlephZero said:
You aren't thinking this through properly.

If there the second set don't inbreed, they are guaranteed to go extinct in one generation.

If they do inbreed, they may or may not go extinct.

So which option does natural selection favor?

Wait a minute now. You're referring to just the two wolly-rhinos and in that particular case, yes, I agree with you: inbreeding is preferred over extinction. But in the wild, there are usually more than two individuals, even whole breeding populations. And in that population, inbreeding is to my knowledge, even the Biology expert on the CBS video about it argued, inbreeding is not done often.

Why then in the wild is inbreeding not done often? The females in the wild, almost exclusively, determines the mating paring: she chooses her mate carefully I believe (from watchin' Nature programs) so I assume she's using some sort of criteria in that selection.

I wish to argue that perhaps the female has a way of detecting inbreeding during her choice for a mate, and in a large breeding population when it's not do or die in the case of the two wolly-rhinos, she avoids inbreeding.
 
Say what?

Not sure what y'all are talking about, but it might help to bear a few facts in mind.

Woolly Rhinos- as in wool, obviously- have been extinct for 10,000 years.
Mating in a zoo is more unnatural than mating between siblings.
If there were two rare rhinos in a zoo, they would have likely grown up with no social modeling. In most mammals prohibitions against close breeding typically come from social learning more than instinct.
Study after study has shown that Wiki is pretty reliable.
 
KaFaraqGatri said:
Not sure what y'all are talking about, but it might help to bear a few facts in mind.

Woolly Rhinos- as in wool, obviously- have been extinct for 10,000 years.

Fine, I made a small mistake. Those two Sumatran rhinos then:

http://www.cbsnews.com/8301-205_162-57594746/ohio-zoo-tries-to-mate-rhino-siblings/rare rhinos

In most mammals prohibitions against close breeding typically come from social learning more than instinct.

That would offer some solution to the problem of why it doesn't happen often.

Can someone contact Jane Goodall? Is she a member of PF? Well why not? I would like her opinion in this matter. I am not yet completely convinced.
 
Last edited by a moderator:
  • #10
Depends upon the species and social network does it not?
 

Similar threads

Graduate Is Mysticism Necessary for Advancing Modern Physics?
  • · Replies 56 ·
2
Replies
56
Views
8K