Global change is expected to impose new selection pressures on natural populations. Phenotypic responses, such as earlier phenology in response to climate warming, have been repeatedly observed in the field. The recent pollinator decline is also expected to change selection on reproductive traits in flowering plants. However, it remains unclear whether short-term adaptation of plant reproductive strategies occurs in response to global change. In this study, we report the evolution of some important reproductive traits of the annual self-incompatible weed Centaurea cyanus. In a common garden experiment, we germinated stored seeds, sampled 18 years apart from the same location, in a region where warmer springs and indices of pollinator decline have been reported. Compared to the ancestral population (1992), our results showed that plants of the descendant population (2010) flowered earlier and also produced larger capitula with longer receptivity and a larger floral display. Q ST -F ST comparisons indicated that natural selection has likely contributed to the evolution of some of the traits investigated. Lower F ST within temporal samples than among spatial samples further suggests a limited role of gene flow from neighbouring populations. We therefore propose that trait shifts could partly be due to adaptation to global change.
Pigmented hemosporidian parasites that do not exhibit erthyrocytic schizogony, and infect birds, chelonians, and squamates, have been classified in various genera over time. These classifications have reflected vertebrate hosts, insect vectors, and variations in morphology and life history observed in representative species. Side-necked turtles ( Podocnemis spp.) from the Peruvian Amazon were screened for hemoparasites and 2 species of hemosporid parasites infecting these hosts were observed. Molecular phylogenetic analysis of these new isolates, along with parasites from lizards, a snake, and a variety of Haemoproteus species from birds from both the Haemoproteus and Parahaemoproteus subgenera, strongly support the separation of the non-avian parasites into a separate genus. The name with precedent for this group is Haemocystidium Castellani and Willey 1909, and we propose that subgeneric classification of Haemocystidium and Simondia be applied to parasites of squamates and chelonians, respectively. We offer a description of Haemocystidium (Simondia) pacayae n. sp. and a redescription of Haemocystidium (Simondia) peltocephali ( Lainson and Naiff 1998 , n. comb.) Morphologically, the parasites are quite similar, with H. pacayae slightly more elongated than H. peltocephali. The discovery and identification of parasite species is urgent, especially in endangered species and wildlife inhabiting rapidly declining ecosystems such as the Amazon.
The structure and connectivity of wildlife host populations may influence zoonotic disease dynamics, evolution and therefore spillover risk to people. Fruit bats in the genus Pteropus, or flying foxes, are the primary natural reservoir for henipaviruses—a group of emerging paramyxoviruses that threaten livestock and public health. In Bangladesh, Pteropus medius is the reservoir for Nipah virus—and viral spillover has led to human fatalities nearly every year since 2001. Here, we use mitochondrial DNA and nuclear microsatellite markers to measure the population structure, demographic history and phylogeography of P. medius in Bangladesh. We combine this with a phylogeographic analysis of all known Nipah virus sequences and strains currently available to better inform the dynamics, distribution and evolutionary history of Nipah virus. We show that P. medius is primarily panmictic, but combined analysis of microsatellite and morphological data shows evidence for differentiation of two populations in eastern Bangladesh, corresponding to a divergent strain of Nipah virus also found in bats from eastern Bangladesh. Our demographic analyses indicate that a large, expanding population of flying foxes has existed in Bangladesh since the Late Pleistocene, coinciding with human population expansion in South Asia, suggesting repeated historical spillover of Nipah virus likely occurred. We present the first evidence of mitochondrial introgression, or hybridization, between P. medius and flying fox species found in South‐East Asia (P. vampyrus and P. hypomelanus), which may help to explain the distribution of Nipah virus strains across the region.
The internal transcribed spacer (ITS) region of ribosomal DNA (rDNA) was used to investigate phylogenetic relationships in Trichilia (Meliaceae). Analyses focused on the neotropical Trichilia and consisted of 112 accessions (95 neotropical Trichilia, 6 African Trichilia and 11 Meliaceae Outgroups). Bayesian and Parsimony approaches demonstrated that the Cuban species T. havenensis is the earliest diverging lineage in the genus. The African species of Trichilia are nested within the neotropical clade. Section Moschoxylun (primarily Amazonian rainforest species) shows significantly lower levels of sequence divergence than section Trichilia (primarily dry/ seasonally dry forest species). Recently diverged rainforest taxa have been documented in several other Angiosperm families and our results therefore confirm this phenomenon.
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