I just came accost this article on the DNA Read the World website.  It was really interesting.  DNA really is helping fill in missing pieces of information in our knowledge.

New Insight Into Horse Evolution Friday, December 11, 2009 18:35 IST

Scientists at the Australian Center for Ancient DNA (ACAD) based at the University of Adelaide are studying ancient DNA from extinct horse species have discovered new evidence on the evolution of Equidae over the past 55 million years.

Only the modern horse, zebras, wild asses and donkey survive today, but many other lineages have become extinct over the last 50,000 years.

“Our results change both the basic picture of recent equid evolution, and ideas about the number and nature of extinct species,” Cooper said.  The study used bones from caves to identify new horse species in Eurasia and South America, and reveal that the Cape zebra, an extinct giant species from South Africa, were simply large variants of the modern Plains zebra.

Study’s lead author, Dr Ludovic Orlando, from the University of Lyon, said that the research team discovered a new species of the distinct, small hippidion horse in South America.  “Previous fossil records suggested this group was part of an ancient lineage from North America but the DNA showed these unusual forms were part of the modern radiation of equid species,” Orlando said.

“This has serious implications for biodiversity and the future impacts of climate change,” Cooper added

This study does not appear to have immediate consequences it continues to add to our knowledge of the world on which we live.  The bones that were studied come from different time periods and many show that these animals became extinct more recently than previously though some as recently as 50,000 years ago.  This study also suggest that we have under-estimated how much a single species can vary over time and space, and mistakenly assumed more diversity among extinct species than were possible.  While most children study Charles Darwin’s theory of Evolution it is sometimes easy to forget that each species changes over time.

This article provides food for though regarding the environment around us and how it has been changing over time.

The study has been published in the Proceedings of the National Academy of Sciences.
National Academy of Sciences