Holocene and Late Pleistocene Bat Fossils (Mammalia: Chiroptera) from Hamilton County, TN, and their Ecological Implications

Chiropteran mandibles from late Pleistocene/Holocene fossil cave localities in Hamilton County were identified in order to examine changes in bat species diversity and population trends over extended periods of time, providing insight into how bats in Southeast Tennessee have responded to major environmental changes over the past 10,000–20,000 years. Generic and species identifications were based on an unpublished key developed by the authors. Measurements of alveolar length (c1–m3) and total length measurements from the symphysis to the condyle were taken for all specimens identified as members of the genus Myotis in an attempt to identify species in this genus. The results of this study failed to confirm those of previous univariate morphological studies, suggesting that multivariate morphometric analyses may be needed to establish a means to differentiate among the species in this genus. Diversity data indicated two patterns of species abundance, with Eptesicus fuscus (Big Brown Bat) dominating some sites and Myotis sp. dominating others. The data suggest, but do not conclusively demonstrate, that a temporal replacement of older Eptesicus faunas by younger, Myotis-dominated faunas has occurred, connected with post-Pleistocene global warming. In addition, a correspondence between human disturbance and bat populations levels was observed. It is very likely that human disturbance has caused bat populations to become extinct in the caves under study, reinforcing the claim of previous researchers that bat population decline is a recent phenomenon that is tightly linksed to human disturbance

Reproductive biology and postnatal development in the tent-making bat Artibeus watsoni (Chiroptera: Phyllostomidae)

In this study we investigated the reproductive patterns and postnatal development in the tent‐making bat Artibeus watsoni. We sampled two populations in the Golfito Wildlife Refuge and Corcovado National Park, south‐western Costa Rica, from June 2003 to March 2005. Most females were pregnant during the months of January and June, and most were lactating in March and July, indicating that this species exhibits seasonal bimodal polyoestry, with the first parturition peak occurring in February–March and the second in June–July. Additionally, we observed a postpartum oestrus following the first parturition, but not after the second. Females entered oestrus again in November–December and had a gestation period of c. 3 months. A female‐biased sex ratio of neonates was observed during the second parturition period, and young were born at 32 and 56% of their mothers' body mass and length of forearm, respectively. Adult proportions in length of forearm were attained faster than adult proportions in body mass, and sustained flight was only possible after 35 days of age, when pups had achieved 100 and 80% of adult length of forearm and body mass proportions, respectively. Weaning and roosting independence occurred when young were c. 30–40 days old, and young females appeared to remain close to their place of birth, at least for their first mating period, whereas adult males were never recaptured near their birth site. In addition, sexual maturity was reached in as little as 3 months in females born during the first parturition period, whereas females born during the second birth period in June–July seemed to reach maturity at 6 months of age. Our results show that A. watsoni belongs to the faster lane of the slow–fast continuum of life‐history variation in bats, which may be attributed primarily to its roosting and feeding ecology.Idea Wild/[]//Estados UnidosConsejo Nacional de Ciencia y Tecnología/[]/Conacyt/MéxicoMinisterio de Ciencia, Tecnología y Telecomunicaciones/[]/MICITT/Costa RicaAmerican Society of Mammalogists/[]/ASM/Estados UnidosCleveland Metroparks Zoo/[]//Estados UnidosBat Conservation International/[]/BCI/Estados UnidosConservation, Food and Health Foundation/[]//Estados UnidosBoston University’s Center/[]//Estados UnidosUniversidad de Costa Rica/[]/UCR/Costa RicaUCR::Sedes Regionales::Sede del Su

Phased, chromosome-scale genome assemblies of tetraploid potato reveals a complex genome, transcriptome, and predicted proteome landscape underpinning genetic diversity

Cultivated potato is a clonally propagated autotetraploid species with a highly heterogeneous genome. Phased assemblies of six cultivars including two chromosome-scale phased genome assemblies revealed extensive allelic diversity including altered coding and transcript sequences, preferential allele expression, and structural variation that collectively result in a highly complex transcriptome and predicted proteome which are distributed across the homologous chromosomes. Wild species contribute to the extensive allelic diversity in tetraploid cultivars, demonstrating ancestral introgressions predating modern breeding efforts. As a clonally propagated autotetraploid that undergoes limited meiosis, dysfunctional and deleterious alleles are not purged in tetraploid potato. Nearly a quarter of the loci bore mutations predicted to have a high negative impact on protein function, complicating breeder’s efforts to reduce genetic load. The StCDF1 locus controls maturity and analysis of six tetraploid genomes revealed 12 allelic variants correlated with maturity in a dosage dependent manner. Knowledge of the complexity of the tetraploid potato genome with its rampant structural variation and embedded deleterious and dysfunctional alleles will be key not only to implementing precision breeding of tetraploid cultivars but also to the construction of homozygous, diploid potato germplasm containing favorable alleles to capitalize on heterosis in F1 hybrids