Histology of a Woolly Mammoth (Mammuthus primigenius) Preserved in Permafrost, Yamal Peninsula, Northwest Siberia

Abstract

In 2007, the baby woolly mammoth (Mammuthus primigenius) named Lyuba was found frozen in the Siberian tundra permafrost along the Yuribey River. She was proclaimed the best-preserved mammoth discovery. As part of the endoscopic examination of Lyuba, tissue samples of hair, muscle, and internal organs were taken. The sectioned biopsies were stained using standard and special histological stains. In general, the microscopic preservation of the tissue was good although no clearly identifiable cell nuclei were found by standard staining methods. Only a few cell nuclei could be identified in some samples when fluorescence stained with DAPI. The best-preserved structures were collagen fibers and muscle tissue, which gave some structural resemblance to the organs. In the hairs, evidence of pigmentation, a scaly surface, diagonal intra-hair structures, and a medulla were seen. Fat droplets could be identified with Sudan Red in the subcutaneous fat sample and in several organs. Bacteria were seen on the lumen side of the small intestine and caecum, and in the liver and lung tissue. In addition, fungi and pollen were seen in the lung sample. In the wall of the caecum and small intestine, blood vessels and nerves were visualized. Iron was identified in the vivianite sample. Some biopsies compared well structurally with the African elephant tissue sections. The histological findings support the theory that Lyuba drowned in muddy water. The microscopic tissue preservation and cell nuclei destruction indicate that Lyuba's body underwent at least one freeze-thaw cycle. Anat Rec, 298:1059Rec, 298: -1071Rec, 298: , 2015. V C 2015 Wiley Periodicals, Inc.

Assessing Metagenomic Signals Recovered from Lyuba, a 42,000-Year-Old Permafrost-Preserved Woolly Mammoth Calf

“…Other possible sources of contamination that consider the tissue specificity we observed are contamination during the sampling procedure or a non-uniform colonization of Lyuba’s tissues by environmental bacteria. Lyuba likely endured at least one cycle of thawing and freezing before discovery [ 25 , 27 ]. This may have affected DNA recovery and the fact that we observed very variable amounts of endogenous DNA in the different tissues could reflect variations in DNA preservation.…”

“…The samples used in this study (donated by Daniel C. Fisher, Museum of Paleontology, University of Michigan, 1109 Geddes Ave., Ann Arbor, MI 48109-1079, USA) were obtained during endoscopical examination, and partial dissections performed in 2008 and 2009, and described in References [ 25 , 27 ]. The authors were not present during these procedures, but received the samples at a later stage.…”

“…Museum of Paleontology, University of Michigan, Ann Arbor, MI, USA). From Reference [ 27 ], reprinted by permission of John Wiley & Sons, Inc. (Hoboken, NJ, USA).…”

“…They conclude that an ice-out flooding during the previous summer is the most likely natural process to have moved the calf to its discovery location. Therefore, Lyuba must have endured at least one cycle of thawing and freezing before discovery, a finding that has also been corroborated by histological analysis [ 27 ].…”

Probing the proboscidea: Lessons from the past

“…Members of this taxonomic group were first observed during the Paleocene epoch (65-55 mya), with adaptive radiations occurring during the Eocene (55-34 mya) and Oligocene (34-23 mya). The mummified remains of several individuals have been recovered and analyzed, yielding a wealth of information about this now-extinct species (Kharlamova et al, 2014(Kharlamova et al, , 2015Palkopoulou et al, 2015;Papageorgopoulou et al, 2015). The only living representatives of this once-successful mammalian order are the elephants (Fig.…”