Another attempt to extract intact DNA from the well-preserved remains of a prehistoric animal failed. Swedish paleontologists, who studied the genome of an 18,000-year-old puppy, could not even determine whether it was a dog or a wolf. Samples of liquid blood taken from the heart of a horse that was in permafrost for 42 thousand years are next for research. Also, specialists havenucleus-like structures of Yuka the woolly mammoth mummy. RIA Novosti figures out what other prehistoric creatures found in Yakutia can provide material sufficient for DNA extraction.