Current hypotheses for primate origins propose that nails and primate-like grasping hands and feet were important early adaptations for feeding in fine branches. Comparative research in this area has focused on instances of convergence in extant animals, showing that species with primate-like morphology feed predominantly from terminal branches. Little has been done to test whether animals with...

In contrast to the abundant fossil record of arctic ground squirrels, Urocitellus parryii, from eastern Beringia, only a limited number of fossils is known from its western part. In 1946, unnamed GULAG prisoners discovered a nest with three mummified carcasses of arctic ground squirrels in the permafrost sediments of the El'ga river, Yakutia, Russia, that were later attributed to a new species,...

The optimal dose of medetomidine-ketamine-buprenorphine was determined in 25 Cape ground squirrels (Xerus inauris) undergoing surgical implantation of a temperature logger into the abdominal cavity. At the end of anaesthesia, the squirrels were given atipamezole intramuscularly to reverse the effects of medetomidine. The mean dose of medetomidine was 67.6 +/- 9.2microg/kg, ketamine 13.6 +/- 1.9...

The North American red squirrel (Tamiasciurus hudsonicus) has expanded its geographic range into the state of Indiana concurrently with a decline in populations of gray squirrels (Sciurus carolinensis) throughout portions of the central hardwoods region of the United States that have been converted to intensive agriculture. Red squirrels construct larder hoards and function as seed predators th...

In this paper, a four-bar mechanism with two flexible links is proposed to be used in a micromechanical flying insect robot wing thorax design for stroke amplification. PZT5H and PZN-PT based unimorph actuators are utilized at the input link of the four-bar. The kinematics and dynamics of the proposed wing strcuture with two parallel four-bar mechanisms are analyzed, and DC forces generated at ...

There is a demand for more progressive restoration directives to regenerate forest ecosystems impacted by harvesting, wildfire, insect outbreaks, and mineral resource extraction. Forest may take many decades even centuries without active silvicultural intervention grow large trees that provide suitable habitat various wildlife species. We tested the hypotheses (H) that, compared with unmanaged ...

Passive infrared technology was used to film diurnal and nocturnal scavenging behavior of brown rats and gray squirrels at the University of Tennessee's Anthropological Research Facility. This direct documentation demonstrated that brown rats modified fat-laden cancellous bone while gray squirrels generally gnawed the thicker bone cortices only after fats had leached away. A case study placed i...

Introduced hosts populations may benefit of an "enemy release" through impoverishment of parasite communities made of both few imported species and few acquired local ones. Moreover, closely related competing native hosts can be affected by acquiring introduced taxa (spillover) and by increased transmission risk of native parasites (spillback). We determined the macroparasite fauna of invasive ...

Twelve percent of 853 California ground squirrels (Spermophilus beecheyi) from six different geographic locations in Kern County, Calif., were found to be shedding on average 44,482 oocysts g of feces(-1). The mean annual environmental loading rate of Cryptosporidium oocysts was 57,882 oocysts squirrel(-1) day(-1), with seasonal patterns of fecal shedding ranging from <10,000 oocysts squirrel(-...

Fox squirrels (Sciurus niger) (five of eight) were infected with West Nile virus (WNV) when challenged by the oral route with 10(2.3) or 10(3.4) plaque forming units (PFU). The mean maximum serum WNV titer of infected fox squirrels was 10(5.1) PFU/mL and ranged from 10(4.6) to 10(5.6) PFU/mL. These levels of viremia are infectious for several mosquito vectors of WNV. This virus was also isolate...