Science & Space :  The Official GrahamHancock.com forums
For all that is Scientifically related to Cosmology and Space. (NB: Please take discussions about UFOs, possible Alien contact, Crop-Circles, Alien Abductions, Planet-X and Niburu to the ‘Paranormal and Supernatural’ Message Board). 
Welcome! Log InRegister
It doesn't take very long for a species compatible with a particular environment to fill it up. A few thousand years is plenty of time. Look at the various "invasive" species around the world now. People have sped up the transfer a bit. Normally it would take major changes such as dropping sea level in an ice age, or continental drift pulling land masses together.

But once a species has a breeding population in any given environment, it can spread very quickly. The "house sparrow" was introduced into North America deliberately in 1852 as a predator for a certain type of moth. They are now common from the Arctic Circle all the way down to Panama. Only the tropical rain forest is inhospitable for them. They managed to get past it and also inhabit South America below the tropics. All this in about 150 years.

Horses are slower breeding and slower moving, but a few thousand years is plenty of time to cross Eurasia if the environment was present for them to survive,

Options: ReplyQuote


Subject Views Written By Posted
Length of time for species migration 1292 Susan Doris 15-Aug-19 12:26
Re: Length of time for species migration 113 Nolondil 15-Aug-19 18:38
Re: Length of time for species migration 151 Aine 15-Aug-19 21:33
Re: Length of time for species migration 164 Susan Doris 16-Aug-19 05:12
Re: Length of time for species migration 105 ianw16 17-Aug-19 01:20
Re: Length of time for species migration 100 Susan Doris 17-Aug-19 05:20
Re: Length of time for species migration 102 Nolondil 17-Aug-19 21:12
Re: Length of time for species migration 187 Susan Doris 18-Aug-19 04:42


Sorry, only registered users may post in this forum.