Nephron progenitor cell populations exist only during embryonic kidney development.
No serious scientist, in fact, believes that genetically pure populations exist.
Unfortunately on 'nearshore' islands neighbouring source populations exist and unaided reinvasion is likely.
RNA viruses have high mutation rates and so their populations exist as dynamic and complex mutant distributions.
Lone hyenas live mostly on carrion, but where large populations exist they form packs and hunt by night.
If this is true, then the following questions arise; 'how many distinct Treg populations exist?' and 'what factors regulate their generation and maintenance?'.
Several distinctive populations exist within the native range of the House Finch, but the evolutionary relationships among these groups needs further study.
Waterfalls create barriers to fish migration, yet hundreds of isolated salmonid populations exist above barriers and have persisted for thousands of years in steep mountainous terrain.
Although guidelines for facial approximations, including those for the eye, are in use in South Africa, limited data on African populations exist to confirm its validity.
Smaller, more isolated populations exist in other countries, including South Africa, Congo (Kinshasa), Zambia, Somalia, Ethiopia, Mali, Niger, Cameroon, Chad, and the Central African Republic.
To the south a substantial Hungarian population extends into Croatia and Serbia, and other large Hungarian populations exist in Austria and Ukraine.
