What you see is what you eat

21 July 2008. Berkeley, California

0730. I met Mary and the dedicated crew of hyena lovers at the Field Station for the Study of Behavior, Ecology, and Reproduction. I will be filming hyenas feeding on their daily diet of bone and ground meat.

Currently, the colony maintains around 32 spotted hyenas (Crocuta crocuta). I am able to film individuals feeding on bone in twenty separate feeding events daily with the help of keepers Marshall and Michelle.

I am using the footages to describe typical bone cracking behavior, including the probable muscles involved in the task, and how they can be better incorporated into computerized models of biting in fossil hyenas.

In other news, I am also examining skulls of spotted hyenas in the Museum of Vertebrate Zoology (University of California, Berkeley). Furthermore, I am spending time in the University of California Museum of Paleontology looking at fossil bone-cracking dogs, and the sabertooth predator Barbourofelis.

From Foggy Berkeley,



The Qaidam hyena cranium discovered

Continued from Part IIa: the quest for the Qaidam hyena cranium

Finding pieces of fossil horse and rhino remains as we headed east, we eventually came to the gulch which leads to our campsite down below. I looked over the cliff at the gathering storm clouds, and decided to take a photo. As I turned around and headed for the trail leading back to camp, I stumbled upon a line of darkened shards glistening in the misty weather.

I bent down to get a better look, and immediately realized that they were broken pieces of tooth enamel, with a dark preservation. Instinctively, I began counting the teeth, and realized that the last tooth in the toothrow is elongate, and has a shearing surface. My heart started pounding, as this meant that the tooth is the fourth upper premolar, the carnassial of a large-sized carnivoran. Putting my face closer to the ground, I also noted that the carnassial is lacking a protocone, a cusp (tooth tip) on the inside of the fourth premolars of many carnivorans. As I looked at the other teeth, I also realized that the tooth just in front of the carnassial is relatively enlarged and robust. "This is a hyena skull " I thought. If so, it would be the first and only carnivore skull to be found in the Qaidam Basin, thereby boosting our confidence in the type of preservation being able to produce complete fossil skulls here.

With intense excitement, I called Gary over, and we came up with a plan to collect the specimen. We did not have enough water and acryloid glue to get the job done. After a short snack break, I started back down the steep 150-foot descent into the wash, to get supplies from camp. We jacketed the specimen that day, but waited until the next morning to give the plaster drying time before extracting it from the ground.

Thinking that the most delicate part of the operation was over, we loaded one of our field vehicles a few days later, and transported all our fish and mammal fossils to Gansu Province for safe-keeping and pick-up on our return trip because we were heading straight to Tibet in August. By the time we had reached western Tibet, we received news that a large flood in Gansu Province had destroyed part of the local museum, and that fossils being stored there are under several feet of mud.

It wasn't until the end of the 2007 field season when I was able to confirm that the plaster jacket containing the hyena cranium was mud-damaged but otherwise intact. I applied for a long-term loan of the specimen from the Chinese Academy of Sciences to bring the jacket back to Los Angeles for preparation.

[the muddy plaster jacket containing the fossil hyena cranium]

[to be continued...]