Pottok the Losino, the Galician, the Landais, and the Monchino horses. Tests have revealed considerable genetic differences between populations in the Northern Basque Country and the Southern Basque Country, leading some to consider them separate breeds. Some claim the Pottok's origins derive from the horses on ancient cave paintings in the area and thus claim to descend from the Magdalenian horses of 14,000–7000 BC. Other link its origins to an influx of horses during the Bronze Age. However, neither of these theories has to date been scientifically verified. Genetic research by the University of the Basque Country's Genetics, Physical Anthropology and
Animal genetic resources for food and agriculture sustainability of a breed and therefore to the potential for successful conservation activities." The Pantaneiro cattle of Brazil are only one example of many at risk of extinction. Despite the importance of animal genetic resources, their diversity has been continually decreasing over time. "Factors as causes of genetic erosion: One of the greatest threats to livestock diversity is pressure from large-scale commercial production systems to maintain only high-output breeds. Recent molecular studies have revealed that the diversity of today's indigenous livestock populations greatly exceeds that found in their commercial counterparts. Climate change and its impact on livestock is being studied.