Evolution in coyotes (Canis latrans) in response to the megafaunal extinctions

Living coyotes modify their behavior in the presence of larger carnivores, such as wolves. However, little is known about the effects of competitor presence or absence on morphological change in coyotes or wolves over long periods of time. We examined the evolution of coyotes and wolves through time from the late Pleistocene, during which many large carnivorous species coexisted as predators and competitors, to the Recent; this allowed us to investigate evolutionary changes in these species in response to climate change and megafaunal extinctions at the end of the Pleistocene. We measured postcranial skeletal morphologies of wolves (Canis lupus) and coyotes (C. latrans) from Pleistocene-aged tar deposits, as well as early, mid, and recent Holocene populations of both. We found few morphological differences between Pleistocene and Holocene wolf populations. Conversely, we found many differences in coyotes: Pleistocene coyotes were larger and more robust than Holocene populations. However, within 1,000 y of the megafaunal extinctions, coyotes are morphologically indistinguishable from modern populations. We cannot attribute these differences directly to climate change because modern coyotes do not follow Bergmann’s rule, which states body size increases with decreasing temperature. Instead, we suggest that Pleistocene coyotes may have been larger and more robust in response to larger competitors and a larger-bodied prey base. Although we cannot separate competition from predator-prey interactions, this study indicates that the effects of biotic interactions can be detected in the fossil record

Mesowear Analysis of the Tapirus Pplkensis Population From the Gray Fossil Site, Tennessee, USA

Various methods exist for measuring and analyzing dental wear patterns in mam-mals, and these patterns have been extensively studied in ungulates. Mesowear has proven useful as a method to compare large numbers of individuals, particularly fossil individuals, observe trends through time or between groups, and estimate paleoenvi-ronmental conditions. Levels of attrition (tooth-on-tooth wear) and abrasion (tooth-on-food wear) can be readily compared by observing the shape of the cusp and relative crown height of the tooth. This study uses a modified method of mesowear analysis, examining actual cusp angles of the population of Tapirus polkensis from the Gray Fossil Site, a densely canopied, hickory and oak dominated forest located in Gray, Tennes-see. Crown height and cusp angle were measured for 38 specimens arranged into eruption series from young juveniles to old adults. Results found a strong correlation between eruption series and cusp angle with a steady increase in mean angle as the individuals increase in age. A strong correlation between cusp angle and crown height was also found. Overall, the population showed relatively low wear rates, as would be expected of a forest-dwelling browser. As a mesowear analysis across all age groups for a population has not been conducted before, this study could be useful for measuring relative wear rates at different life stages and could be applied across other com-munities

The First Eocene Rodents From the Pacific Northwest, USA

The Oligocene and Miocene faunas of the John Day Basin are diverse and very well-studied, including a large number of small mammal species. Though Eocene floras from Oregon are well-known, Eocene faunas include relatively few taxa from only two described localities in the Clarno area. The first Eocene rodents from the John Day Basin also include the first ischyromyids from the Pacific Northwest. Several rodent incisors were recovered from the Hancock Mammal Quarry at Clarno, representing the first rodent specimens known from the Clarno Formation. The Hancock Mammal Quarry lies between tuffs dated 42.7 and 39.22 Ma, meaning these rodents are latest Uintan or earliest Duchesnean in age. Several ischyromyids are also described from the Big Basin Member of the John Day Formation. From a Duchesnean locality between tuffs dated 39.22 and 38.4 Ma a single tooth of Pseudotomus was recovered, which is as large as any known ischyromyid. Another Big Basin Member site yielded a new genus and species of ischyromyid. That site lies above an ash dated 36.21 Ma and biostratigraphy confirms a Chadronian age. These rodents help fill important gaps in the fossil record of the John Day Basin and will facilitate comparisons with other Eocene sites in North America and Asia

The Last Fossil Primate in North America, New Material of the Enigmatic \u3ci\u3eEkgmowechashala\u3c/i\u3e From the Arikareean of Oregon

OBJECTIVE: Primates were common in North America through most of the Eocene, but vanished in the Chadronian, about 35 million years ago. In the Arikareean, about 6 million years later, the enigmatic primate Ekgmowechashala appeared in the Great Plains and Oregon. This taxon shows little resemblance to other North American primates and its phylogenetic position has long been debated. New material of this taxon allows a revised assessment of its age and how it is related to other primates. METHODS: Recently collected Ekgmowechashala specimens from the Turtle Cove Member of the John Day Formation in Oregon are described. These specimens are compared to previously collected material from South Dakota and Nebraska, as well as other fossil primates from North America and Asia. RESULTS: Study of the John Day material allows diagnosis of a new, distinct species. Comparison of Ekgmowechashala to a pair of recently described Asian primates, Muangthanhinius and Bugtilemur, suggests that it is a strepsirrhine adapiform, rather than an omomyid. The well-defined stratigraphy and dated marker beds of the Turtle Cove Member provide a refined age for Ekgmowechashala occurrences in Oregon, during the Oligocene (early Arikareean). CONCLUSIONS: The age and morphology of these ekgmowechashaline taxa suggest that the group originated in Asia and dispersed to North America in the Oligocene, after the extinction of other primates in North America. Contemporaneous occurrences of Ekgmowechashala in Oregon and the Great Plains indicate the last non-human primates vanished in North America about 26 million years ago

The earliest dipodomyine heteromyid in North America and the phylogenetic relationships of geomorph rodents

Dipodomyine heteromyids (kangaroo rats and mice) are a diverse group of aridadapted ricochetal rodents of North America. Here, a new genus and species of a large dipodomyine is reported from early Miocene-aged deposits of the John Day Formation in Oregon that represents the earliest record of the subfamily. The taxon is known from a single specimen consisting of a nearly complete skull, dentary, partial pes, and caudal vertebra. The specimen is characterized by a mosaic of ancestral and highly derived cranial features of heteromyids. Specifically, the dental morphology and some cranial characteristics are similar to early heteromyids, but other aspects of morphology, including the exceptionally inflated auditory bullae, are more similar to known dipodomyines. This specimen was included in a phylogenetic analysis comprising 96 characters and the broadest sampling of living and extinct geomorph rodents of any morphological phylogenetic analysis to date. Results support the monophyly of crown-group Heteromyidae exclusive of Geomyidae and place the new taxon within Dipodomyinae. The new heteromyid is the largest known member of the family. Analyses suggest that large body size evolved several times within Heteromyidae. Overall, the morphology of the new heteromyid supports a mosaic evolution of the open-habitat adaptations that characterize kangaroo rats and mice, with the inflation of the auditory bulla appearing early in the group, and bipedality/ricochetal locomotion appearing later. We hypothesize that cooling and drying conditions in the late Oligocene and early Miocene favored adaptations for life in more open habitats, resulting in increased locomotor specialization in this lineage over time from a terrestrial ancestor

Muknalia is a Collared Peccary (Pecari Tajacu): A Reply to Stinnesbeck et al.

Several years ago, a new genus and species of peccary, “Muknalia minima”, was described from the Pleistocene of Mexico. We previously examined that specimen and concluded that it was synonymous with the extant collared peccary, Pecari tajacu, but that taxonomic revision is rejected by the authors of the original study (this volume). Here, we provide further analysis of “Muknalia” and expand on previous evidence from both morphology and taphonomy that support synonymy with P. tajacu. We argue that morphological features, both in terms of size and shape, that were used to diagnose “Muknalia” all fall within the range of variation of the extant P. tajacu, or are a consequence of taphonomic modification, including human handling

Topical Rapamycin Therapy to Alleviate the Cutaneous Manifestations of Tuberous Sclerosis Complex

Background and Objectives: Facial angiofibromas are disfiguring facial lesions, present in up to 80% of patients with tuberous sclerosis complex. Recent elucidation of the complex cell signaling pathways that are disrupted in tuberous sclerosis indicates that rapamycin may be successful in alleviating the appearance of these lesions. The objectives of the current study were to evaluate the safety of topically applied rapamycin in patients with tuberous sclerosis complex and to determine its potential effectiveness in treatment of facial angiofibromas. Patients and Methods: The study was a prospective, randomized, double-blind, placebo-controlled study performed at the University of Texas Health Science Center at Houston. Study subjects were recruited from the patient populations at the University of Texas Tuberous Sclerosis Center of Excellence. All subjects were over the age of 13 years and had a diagnosis of tuberous sclerosis complex. Subjects were excluded if they were using any form of rapamycin or if they were pregnant. Study subjects applied the study product to their facial angiofibromas nightly for a duration of 6 months. The investigational product contained one of three doses of rapamycin compounded with Skincerity®: (i) no rapamycin; (ii) 1 mg of rapamycin per 30 cc (0.003%); or (iii) 5 mg of rapamycin per 30 cc (0.015%). Plasma rapamycin concentrations were measured monthly to test for systemic absorption. Complete blood counts were performed monthly to test for anemia, neutropenia, or thrombocytopenia. Upon completion of the trial, subjects were asked if the formulation had improved the appearance of their facial angiofibromas. Results: Twenty-three subjects completed the study. There was no detectable systemic absorption of rapamycin (all blood concentrations were <1.0 ng/mL). There were no significant changes in white blood cell, red blood cell, or platelet counts. Seventy-three percent of subjects in the treatment arms versus 38% of subjects in the placebo arm reported a subjective improvement in the appearance of their facial angiofibromas. Conclusion: The application of low-dose topical rapamycin (0.003–0.015%) to the face can safely decrease the appearance of facial angiofibromas in patients with tuberous sclerosis complex

Association of blood pressure variability and neurocognition in children with chronic kidney disease

Children with chronic kidney disease (CKD) and hypertension have increased blood pressure variability (BPV). Increased BPV has been associated with lower neurocognitive test scores in adults. Children with CKD are at risk for decreased neurocognitive function. Our objective was to determine if children with CKD and increased BPV had worse performance on neurocognitive testing compared with children with CKD and lower BPV

Neurocognitive Function in Children with Primary Hypertension

To compare neurocognitive test performance of children with primary hypertension to that of normotensive controls

The Student Movement Volume 105 Issue 13: AU Students Speak out Against Anti-AAPI Violence

NEWS James White Library Offers Useful Resources to Students, Amanda Cho The Office of Diversity and Inclusion and the Center for Faith Engagement Host Asian American and Pacific Islander Forum, Jenae Rogers The Office of Research and Creative Scholarship Hosts the Undergraduate Research and Honors Scholar Symposium, Caralynn Chan PULSE My Experience with Robinhood, Matthew Jarrard Nature Spots on Campus, Gloria Oh Pilipino Culture Night, Interviews by Masy Domecillo HUMANS Interview with T Bruggemann, Terika Williams Interviewing Andrews University\u27s AAPI Students on Allyship, Interviewed by Abigail Lee Senior Spotlight: Hailey Kim, Interviewed by Celeste Richardson ARTS & ENTERTAINMENT Creative Spotlight: Marcel Mattox, Interviewed by Joshua Deonarine AAPI Documentaries You Need to Watch, Megan Napod Asian Women, Courtesy of Hollywood, Hannah Cruse IDEAS Flying Sparks: The Implications of the Rise in AAPI Hate, Alannah Tjhatra The Three P\u27s of Perspective, Kyara Samuels THE LAST WORD Respecting Apoliticism, Daniel Selfhttps://digitalcommons.andrews.edu/sm-105/1017/thumbnail.jp