on โ26-12-2014 11:04 AM
on โ26-12-2014 07:37 PM
@the_great_she_elephant wrote:I am also saying that while dog breeds have evolved over the years (and cats, horses and whatever else) - NONE OF THEM HAVE EVER CROSSED THE SPECIES BARRIER. ** except I guess horses and donkeys but they only give neuter Mules, so NO ongoing generations.
Somehow I don't think creating a new species is the object of the exercise in dog breeding..
even if it were - it would fail wouldn't it??
you know what I am trying to say - how does evolution cater for completely new species - I am talking about dogs because I am was a breeder for 30 years. No matter how many generations of breeding take place - two elephants is not going to produce anything else but an elephant - the resulting progeny may be smaller or bigger depending on whether there is some control over breeding just the big elephants or just the small elephants BUT it will still be an elephant.
on โ26-12-2014 07:52 PM
Evolution is all about adaptation - from small Asian elephants to giant African elephants to extinct woolly mammoths. They don't necessarily create new species because we categorize them into species and sub species because we haven't been around long enough to witness mass changes. So dolphins and whales once land living creatures (evident by their still existent but detached leg bones) are still classified mammals. Why seals vary because some still retain leg/finger bones and claws while some have evolved to have them completely made redundant and gone. Even mankind is evolving due to such factors as diseases that have been controlled means we are becoming larger in size (disease usually stunts growth so we are adapting to a new environment)
on โ26-12-2014 08:01 PM
I know this is a bit off topic but can someone tell me how this fits together.
wiki says:
Family: Elephantidae ; Order: Proboscidea;
2 Species African Elephant (Loxodonta africana) and Asian Elephant (Elephas maximus).
but then, in another spot:
Only two genera, Loxodonta (African elephants) and Elephas (Asiatic elephants), are living.
so are the African and Indian elephants separate species or separate genus?
where does Genus: ; Species: fit into Family , Order etc
on โ26-12-2014 08:03 PM
@para-slights wrote:Evolution is all about adaptation - from small Asian elephants to giant African elephants to extinct woolly mammoths. They don't necessarily create new species because we categorize them into species and sub species because we haven't been around long enough to witness mass changes. So dolphins and whales once land living creatures (evident by their still existent but detached leg bones) are still classified mammals. Why seals vary because some still retain leg/finger bones and claws while some have evolved to have them completely made redundant and gone. Even mankind is evolving due to such factors as diseases that have been controlled means we are becoming larger in size (disease usually stunts growth so we are adapting to a new environment)
this is all too much - sea life came onto land and now land life went into the sea??? where will it all end?
on โ26-12-2014 08:11 PM
@rabbitearbandicoot wrote:all of those civilizations then are less than 6,000 years old? Are there any records of civilizations prior to that?
Although agriculture has been around for about 12,000 years,it wasn't until about 6000 or so years ago that man first got on top of farming practices.Science at work again.Prior to that the land was used for monoculture.This made the soils sterile,which necessitated a semi-nomadic existence. Once farming practices had improved,cities and civilizations formed.Other necessary developments like writing etc came much later.
on โ26-12-2014 08:18 PM
got it:
Domain > Kingdom = animalia / Plantae > Phylum > Class > Order > Family > Genus > Species
that will do for now - otherwise the brain starts to hurt .
on โ26-12-2014 08:28 PM
LOL it ends when the world ends or at least stagnates lol. While changes still occur so will evolution. Why Australia for instance when almost completely a tropical forest and larger in size could support large mega fauna but as it drifted and dried that mega fauna died off and the smaller more adoptable ones took their place. So species adapt, die, migrate or completely change
on โ26-12-2014 09:57 PM
@rabbitearbandicoot wrote:
you know what I am trying to say - how does evolution cater for completely new species - I am talking about dogs because I
amwas a breeder for 30 years. No matter how many generations of breeding take place - two elephants is not going to produce anything else but an elephant - the resulting progeny may be smaller or bigger depending on whether there is some control over breeding just the big elephants or just the small elephants BUT it will still be an elephant.
Yes, that is true, but in every generation there are some little mutations, and if populations are separated, after hundreds of thousands of years the difference can be such that they will result in different species, and even if they somehow met each other again they will not be able to crossbreed, because the number of chromosomes mutated. That is how species happen. But within each species the mutations and selection for the fittest = best suited to the circumstances, in which they live, results in animals changing in size, or how much coat they have etc. Dogs are unique in the way they change quite fast and that is why were able to create all the different breeds in mere 10 000 years. But that is far too short time to change the number of chromosomes, which is the change that makes a different species.
on โ26-12-2014 10:25 PM
so, can an African elephant breed with an Indian elephant?
Apart from the distance between them of course.
on โ26-12-2014 10:31 PM
Only if he promises to respect her, and call her in the morning!