Our team has just published the discovery and description of a large fossil cane rat from the Al Gharbia region of Abu Dhabi Emirate, U.A.E. Cane rats today are only known from two species living in Africa, so it is very interesting to know that they once roamed across parts of the Arabian Peninsula.
The fossil cane rat is around 7 million years old and comes from the Baynunah Formation which is a sequence of river-deposited sands that are exposed in the western region of Abu Dhabi Emirate.
We named the new fossil rodent Protohummus dango. The genus name Protohummus honors chick peas (Arabic: hummus) because the fossil teeth of this rodent were large, somewhat round, and stained yellowish-brown by the fossilization process, coming to resemble chick peas. The species name dango is from that of a local Emirati dish made of boiled chick peas.
From an evolutionary analysis, we concluded that Protohummus is a sort of ‘missing link’ in the evolution of the cane rat family (Thryonomyidae). Previous thryonomyid fossils were either already very similar to the living species, or else differed in many features. At 7 million years in age, Protohummus from Arabia fills an evolutionary gap between the thryonomyid Paraulacodus, an older, more conservative form known from Africa and Pakistan, and the living Thryonomys, known only from Africa.
The study was published in the scientific journal Naturwissenschaften. A pdf copy of the article is available here.
Here’s also a link to an article by The National newspaper about the discovery.
Study citation:
Kraatz, B. P., Bibi, F., and Hill, A., and Beech, M., 2013, A New Fossil Thryonomyid from the Late Miocene of the United Arab Emirates and the Origin of African Cane Rats. Naturwissenschaften. DOI 10.1007/s00114-013-1043-4
Can you spot the tooth of Protohummus? It’s the yellow-brown round thing in the middle of the plate. (image: F. Bibi CC BY-SA-NC)
The living African cane rat. The new Arabian fossil cane rat Protohummus was just as large (image: A. Zizo wikimedia commons)
In order to find fossil rodents, we spent many weeks sieving through several tons of ancient river sands (image: F. Bibi CC BY-NC-SA)
Our evolutionary analysis (‘A’) shows the position of Protohummus among fossil and living cane rats.
Tree ‘B’ below shows the evolution of cane rats over the last 17 million years. Protohummus is intermediate between ancient extinct cane rats (Paraulacodus) and living cane rates (Thryonomys).
After sieving, we have to search through the remaining bits of sand and stone to find fossils (image: CC BY-NC-SA F. Bibi)
Scanning Electron Microscope (SEM) images of the fossil teeth of Protohummus.
Map of the Al Gharbiah region of Abu Dhabi Emirate showing sites where remains of Protohummus were found.
Two teeth of Protohummus, ruler is in centimeters (and millimeters). Though they look small, these are large teeth for a rodent (image: F. Bibi CC BY-SA-NC)
dango
