|
1-10 of 14 messages
|
Page 1 of 2
Next
|
|
A question on evolution (or devolution)
|
Reply
|
|
by Existential on February 17, 2009
|
Mail this to a friend!
|
I came across an interesting poll this morning on reptilegeeks.com, and now I'm very curious to see everyone's opinion on the subject.
In essence, the poll was asking about devolution of venomous snakes; whether a hot kept in captivity for so long could lose it's venom glands.
I have seen mutations where snakes become 'scaleless,' so why not 'venomless?' In captivity, these mutations don't make much of a difference, simply because the animal will have as much chance to eat as anyone else.
Another thing, what would a 'venomless' mutation look like? Would the hot keep it's hypodermic fangs? And what about the shape of it's head?
Lastly, instead of a hot losing the whole venom gland, could a line of hots gradually lose potency in venom?
I am very curious now!
|
| |
|
RE: A question on evolution (or devolution)
|
Reply
|
|
by Crotalusssp on February 17, 2009
|
Mail this to a friend!
|
A loss of potency of venom would be a slim possibility over many generations. As far as a complete reversal and loss of venom production and delivery system, this would be HIGHLY unlikely even after 1000's of generations.
Charles
|
| |
|
RE: A question on evolution (or devolution)
|
Reply
|
|
by BobH on February 17, 2009
|
Mail this to a friend!
|
|
Good answer Charles, however I think that if we had a way to easily assay the venom toxicity and could very selectively breed for the reduced virulence,we could significantly reduce the toxicity in maybe only 25-30 generations. Anybody want to devote the rest of their life to this one?
|
| |
|
RE: A question on evolution (or devolution)
|
Reply
|
|
by earthguy on February 17, 2009
|
Mail this to a friend!
|
|
I have just one thing to add...Evolution has no direction and thus there is no Devolution. You could hypothecially find the gene(s) that produce(s) the venom and turn it off...but that is genetic engineering on an individual (or group of individuals) - not Evolution
|
| |
|
RE: A question on evolution (or devolution)
|
Reply
|
|
by FSB on February 17, 2009
|
Mail this to a friend!
|
|
Thanks, Josh.... there are at least as many, if not more, misconceptions about evolution than there are about snakes, and most people (especially Darwin detractors) have a very poor grasp of the subject. This has been the case from the beginning, when Darwin's theory was widely misconstrued as implying that "Man was descended from the apes." This is impossible.... what was determined is that humans and apes have a common ancestor, but neither one could have evolved from the other. Actually, Darwin did not "invent" the idea of evolution, he merely observed, and described, the mechanism of natural selection. He never used the phrase "survival of the fittest" and that really isn't what it's all about. Evolution doesn't necessarily "improve" an organism, nor does it proceed towards a goal (as Josh pointed out). That idea, known as Teleology, was debunked and dismissed long ago. Animals do not "evolve" a structure independently of the rest of the animal (such as the long neck of the giraffe) for a particular purpose, and nothing "devolves." It's far too much to take on in a post, actually, and I almost wish I hadn't started this. There are plenty of good books on the subject, though, beginning with On the Origin of Species.
|
| |
|
RE: A question on evolution (or devolution)
|
Reply
|
|
by Cro on February 17, 2009
|
Mail this to a friend!
|
Here are a couple of interesting articles, that, though not about reptiles, might be of interest on this topic.
http://www.sciencedaily.com/releases/2008/11/081107071822.htm
http://www.sciencedaily.com/releases/2009/01/090126203207.htm
Best Regards
John Z
|
| |
|
RE: A question on evolution (or devolution)
|
Reply
|
|
by Existential on February 17, 2009
|
Mail this to a friend!
|
Thanks for all the replies, guys! As far as Darwin's "Origin", I've been meaning to get around to reading it. I'm afraid that my ideas of evolution come from my deductions of what I learned in school and I what I researched for myself. My personal idea of evolution is that it is restricted to species, and that mutations amongst species will give advantages, thus more chance of finding food and reproducing. Is this close at all to the official theory?
As for the original question of losing venom, I wasn't sure if this could happen through some mutation in genes, without human intervention. Of course, this would prove disadvantageous in the wild, and thus probably wouldn't be carried on.
Just thought it was an interesting question.
Thanks again, guys, and I'll check out those links.
|
| |
|
RE: A question on evolution (or devolution)
|
Reply
|
|
by LarryDFishel on February 17, 2009
|
Mail this to a friend!
|
>...mutations amongst species will give advantages...
The reasonably short (and incomplete) version is:
A mutation causes an offspring to be different from its parents.
1)Occasionally, that difference is advantageous for that species in that environment (increases the chances of it's line continuing, possibly for very subtle reasons).
If so, that mutation MAY be carried on (or that specimen may be eaten before it breeds for instance).
2)Sometimes the difference may not be advantageous but also not (or only very slightly) disadvantageous, in which case that gene might still continue, either by random chance or because it happened to occur in a line that was already dominant for some other reason.
3)Sometimes it is significantly disadvantageous in which case it will most likely be weeded out (unless it gets government assistance and fertility treatments).
4)Sometimes the difference is completely incompible with life and the organism either dies before or shortly after being born/hatched.
Option 1 is probably less common than 3 and 4 by a huge margin. I don't know how common 2 is, but I'm sure someone's made a career out of studying the question...
|
| |
|
RE: A question on evolution (or devolution)
|
Reply
|
|
by MikeB on February 19, 2009
|
Mail this to a friend!
|
|
Interesting question . . . first, evolution via adaption works over many many generations, so you'd really be talking about a guided breeding project that would extend for, say 5,000 years. Second, venom in many hots is not just for prey capture, but it also begins the digestive process, so even if a mouse or rat was dropped conveniently in front of a captive hot every week, the snake would still retain an adaptive advantage in injecting it with venom.
|
| |
|
RE: A question on evolution (or devolution)
|
Reply
|
|
by FSB on February 19, 2009
|
Mail this to a friend!
|
Actually, anything that takes place in captivity is not going to involve natural selection, of course, so whatever we're talking about here, it is not really "evolution" in the usual sense.
Much to my dismay, my son is currently going through a Pokemon phase that is about to drive me nuts. I try to be very tolerant of whatever he wants to get into, since I certainly put my parents through a lot, but I have a real low tolerance for Japanese animation.
What's really bothersome to me though is how they misuse the term "evolve," in the sense that a pokemon creature can come into contact with some crystal or something and then it "evolves" into a more advanced or stronger form of pokemon. I've explained to him that it is impossible for an individual organism to evolve... an organism that changes form during its lifetime, such as a caterpillar turning into a butterfly or a tadpole into a frog, is undergoing metamorphosis, not evolution. One must be constantly vigilant against the nitwits in show-biz who are constantly feeding our kids bad information.
|
| |
|
Email Subscription
You are not subscribed to this topic.
Subscribe!
My Subscriptions
Subscriptions Help
Check our help page for help using
, or send questions, comments, or suggestions to the
Manager.
|
