AtomicHorror Registered User
#61

Scofflaw said:
There's a good chapter on domestication in Jared Diamond's Guns, Germs, and Steel - all the domesticated species share certain traits: unfussily herbivorous, fast-growing, easily breeding, non-violent disposition, herd together when panicked rather than bolting, not overly territorial, and living in hierarchical herds. Lack of any one of those characteristics has meant domestication has been unsuccessful.

cordially,
Scofflaw


Yep, with the notable exceptions of dogs and cats...

bogwalrus Registered User
#62

things are getting much clearer for me now. tnx again for your time.

AtomicHorror Registered User
#63

bogwalrus said:
things are getting much clearer for me now. tnx again for your time.


No problem. If you have any other questions feel free to ask

Scofflaw Registered User
#64

AtomicHorror said:
Yep, with the notable exceptions of dogs and cats...


Which form interesting exceptions, since they're not domesticated in quite the same way as the others - although, if one thinks about it, the dog, like the pig, is actually omnivorous, but otherwise fits the bill (as does the pig). Cats, of course, don't, but I suspect not everyone would agree that cats are domesticated, as opposed to merely being domestic.

cordially,
Scofflaw

Galvasean Registered User
#65

Apparently the dog (or perhaps wolf) was the first animal to be domesticated. The idea goes that initially early humans would follow wolves which would lead them (inadvertently) to prey. The humans with their weapons were capable of taking much larger prey than the wolves could. Once the humans took their fill the wolves could scavenge what remained. Apparently then over time the symbiosis grew, becoming more organized.

Not so sure about cats. Perhaps we noticed having them around kept away rats etc.

Galvasean Registered User
#66

Could this be an example of evolution in action?

http://dsc.discovery.com/news/2008/07/25/whale-shark-size.html

Natural selection favoring the small it would seem.

AtomicHorror Registered User
#67

Galvasean said:
Could this be an example of evolution in action?

http://dsc.discovery.com/news/2008/07/25/whale-shark-size.html

Natural selection favoring the small it would seem.


Various shark species have been shrinking over the 400-million odd years that they've been around. Perhaps the more recent selective pressure is something to do with a shortage of food... The article cites human targeting of the larger individuals though.

AtomicHorror Registered User
#68

Bottle_of_Smoke said:
anyone got a decent article on how evolution creates new/different species?


Right, try this:

http://thebiologista.blogspot.com/2008/07/great-wormtown-spade-disaster-part-1.html

It's a couple of pages but it's a nice no-jargon kinda storybook version of speciation. It brings in the effects of mutation, habitat fragmentation and the main mechanisms of evolution itself and it shows how they combine to end up generating two species from one. It's done in a very basic, almost piss-take style but as a jumping-off point for discussion of speciation it's pretty good.

Hope that's a help.

Scofflaw Registered User
#69

Galvasean said:
Could this be an example of evolution in action?

http://dsc.discovery.com/news/2008/07/25/whale-shark-size.html

Natural selection favoring the small it would seem.


It's interesting to consider that, over time, anthropogenic habitat fragmentation might well lead to a form of 'virtual' island dwarfism. I'm not sure if that has had time to develop anywhere as yet, though - possibly somewhere like England or other long-established anthropogenic environments.

cordially,
Scofflaw

jtsuited Registered User
#70

bloody great idea for a thread. surprised it was never here before.

interesting thing in the bees article about how competing for social rank causes the brain to develop.
Would that mean that stratified society is actually making us more intelligent as we are forced to compete?

Asiaprod Why is Bellybutton Fluff always Blue
#71

Scofflaw said:
It's interesting to consider that, over time, anthropogenic habitat fragmentation might well lead to a form of 'virtual' island dwarfism. I'm not sure if that has had time to develop anywhere as yet, though - possibly somewhere like England or other long-established anthropogenic environments.

cordially,
Scofflaw

See the lost tribe of Pilau (National Geographic)
[Edit] Oops, my bad, was not anthropogenic, but it is interesting

AtomicHorror Registered User
#72

jtsuited said:
bloody great idea for a thread. surprised it was never here before.

interesting thing in the bees article about how competing for social rank causes the brain to develop.
Would that mean that stratified society is actually making us more intelligent as we are forced to compete?


That would depend on the nature of the competition. In modern human society, competition is almost entirely based on intelligence, but it's hard to say if we can yet observe evolutionary changes based on this due to the relatively short time scale.

Dave! Moderator
#73

Hey Atomic Horror, I sent you a PM!

1 person has thanked this post
Galvasean Registered User
#74

AtomicHorror said:
Various shark species have been shrinking over the 400-million odd years that they've been around. Perhaps the more recent selective pressure is something to do with a shortage of food... The article cites human targeting of the larger individuals though.


But would it not be unreasonable to speculate that the hunting of larger specimens (to get the bigger fins), in a sense favouring them over the smaller ones, could be taking them out of the gene pool leaving the smaller ones to populate the species?
Of course this is all a bit hypothetical since whale shark breeding patterns are poorly understood at best. Their young and mating habits are virtually unknown. We don't yet know what age/size they reach sexual maturity at.

AtomicHorror Registered User
#75

Galvasean said:
But would it not be unreasonable to speculate that the hunting of larger specimens (to get the bigger fins), in a sense favouring them over the smaller ones, could be taking them out of the gene pool leaving the smaller ones to populate the species?


It's rather hard to say whether the reduction in the average size is actually representative of a change in the frequency of any specific genes without more extensive work. If larger sharks are being targeted and killed then we would fully expect the average shark size to reduce for that reason alone.

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