Research Training Program

Christian Miguel Pinto Baez
Pontificia Universidad Católica del Ecuador
Quito, Ecuador

Al Gardner, Ph.D.
Supervising Scientist
Vertebrate Zoology - Mammals

“RTP: a re-discovery of the love for science, and a career-defining experience”

Identity of an atypical bear from Alaska: The first documented wild hybrid bear (Ursus americanus X Ursus arctos)?

In 1986 a giant bear was killed by a hunter in Alaska, and the skull was sent to the National Museum of Natural History to confirm his identity, because if it was a true black bear it could be the largest black bear ever recorded. However, this bear shows characteristics of brown and black bears. In order to identify this unusual bear skull, we analyzed the shape of the last upper molar, one of the most important taxonomic structures in bears. We compared a representative sample of black and brown bears to establish the differences. Once we could see the differences, we included the anomalous bear in our analysis. Despite his big skull size (one of the largest recorded, even for brown bears), the bear matched with the group of black bears. However, when we included tooth size and fur color in our analyses, the bear fit just in middle between the two species. These differences strongly suggest that this specimen is a hybrid. This assumption will be collaborated with genetic studies. The data obtained in this study indicate that the following questions remain unanswered: What is the significance of hybrids on natural populations? What is the evolutionary effect of bear hybrids for the parental species? Evolutionary death? Speciation? Where are the limits for species?

… In science there are always more questions than answers.

This research was supported by a grant from the Smithsonian Latino Initiatives Fund.

Letter of gratitude