Assuming the Denisovans, Neanderthals, and humans were able to interbreed, what does this tell you about their species status according to the biological species concept?

Is the frog an ancestor of humans? Explain.

Brown et al. and Morwood et al. reported in 2004 that they had found skeletal remains of a previously unknown type of hominin, now dubbed Homo floresiensis, on the Indonesian island of Flores. These hominins were small (approximately 1 m tall) with small braincases (approximately 380 cm3) as compared with other hominins. The remains of H. floresiensis were found alongside handmade stone tools and the remains of dwarf elephants that also inhabited the island, suggesting that H. floresiensis was able both to make tools and to coordinate the hunting of animals much larger than itself. H. floresiensis is estimated to have lived at the site where the remains were found from 700,000 years ago to 60,000 years ago. Which would be the most feasible method of figuring out to which other hominin species H. floresiensis was most closely related? Compare the average body size of H. floresiensis to that of each of the other hominin species. Compare the type of prey hunted by H. floresiensis to that…

What specific evidence do paleoanthropologists cite to support the arguments that Neanderthals had a tendency to inbreed (extreme endogamy)? What are the speculated reasons for this practice?