ossils of birds not clearly assignable to either hummingbirds or a related extinct family, the Jungornithidae, have been found at the Messel pit and in the Caucasus, dating from 35 to 40 million years ago; this indicates that the split between these two lineages indeed occurred around that time. The areas where these early fossils have been found had a climate quite similar to that of the northern Caribbean or southernmost China during that time. The biggest remaining mystery at present is what happened to hummingbirds in the roughly 25 million years between the primitive Eurotrochilus and the modern fossils. The astounding morphological adaptations, the decrease in size, and the dispersal to the Americas and extinction in Eurasia all occurred during this timespan. DNA-DNA hybridization results suggest that the main radiation of South American hummingbirds took place at least partly in the Miocene, some 12 to 13 million years ago, during the uplifting of the northern Andes. In 2013, a 50-million-year-old bird fossil unearthed in Wyoming was found to be a predecessor to both hummingbirds and swifts before the groups diverged. Lists of genera and species List of hummingbird species, sortable alphabetically by common name, binomial name, or taxonomic sequence Evolution Hummingbirds are thought to have split from other members of Apodiformes, the insectivorous swifts (family Apodidae) and treeswifts (family Hemiprocnidae) about 42 million years ago, probably in Eurasia. Despite their current New World distribution, the earliest known species of humming bird are known from the early Oligocene (Rupelian ~34-28 million years ago) of Europe, belonging to the genus Eurotrochilus, which is very similar in its morphology to modern hummingbirds. A phylogenetic tree unequivocally indicates that modern hummingbirds originated in South America, with the last common ancestor of all living hummingbirds living around 22 million years ag o. A map of the hummingbird family tree – reconstructed from analysis of 284 of the world's 338 known species – shows rapid diversification from 22 million years ago. Hummingbirds fall into nine main clades, the topazes, hermits, mangoes, brilliants, coquettes, the giant hummingbird, mountaingems, bees, and emeralds, defining their relationship to nectar-bearing flowering plants and the birds' continued spread into new geog