Biodiversität und Klima Forschungszentrum (BiK-F)
Refine
Year of publication
Document Type
- Article (271)
- Preprint (8)
- Part of Periodical (4)
- Book (3)
- Contribution to a Periodical (3)
- Doctoral Thesis (3)
- Conference Proceeding (1)
- Review (1)
Language
- English (280)
- German (11)
- Multiple languages (3)
Has Fulltext
- yes (294)
Is part of the Bibliography
- no (294)
Keywords
- climate change (9)
- Invasive species (7)
- Phylogeny (6)
- Biodiversity (5)
- Biogeography (5)
- phylogeny (5)
- taxonomy (5)
- Climate change (4)
- Ecological modelling (4)
- West Africa (4)
Institute
- Biodiversität und Klima Forschungszentrum (BiK-F) (294)
- Senckenbergische Naturforschende Gesellschaft (189)
- Institut für Ökologie, Evolution und Diversität (130)
- Biowissenschaften (113)
- Geowissenschaften (45)
- Medizin (13)
- Geographie (12)
- Institut für sozial-ökologische Forschung (ISOE) (7)
- Präsidium (5)
- LOEWE-Schwerpunkt für Integrative Pilzforschung (4)
Background: Studies on allele length polymorphism designate several glacial refugia for Norway spruce (Picea abies) in the South Carpathian Mountains, but infer only limited expansion from these refugia after the last glaciation. To better understand the genetic dynamics of a South Carpathian spruce lineage, we compared ancient DNA from 10,700 and 11,000-year-old spruce pollen and macrofossils retrieved from Holocene lake sediment in the Retezat Mountains with DNA extracted from extant material from the same site. We used eight primer pairs that amplified short and variable regions of the spruce cpDNA. In addition, from the same lake sediment we obtained a 15,000-years-long pollen accumulation rate (PAR) record for spruce that helped us to infer changes in population size at this site. Results: We obtained successful amplifications for Norway spruce from 17 out of 462 pollen grains tested, while the macrofossil material provided 22 DNA sequences. Two fossil sequences were found to be unique to the ancient material. Population genetic statistics showed higher genetic diversity in the ancient individuals compared to the extant ones. Similarly, statistically significant Ks and Kst values showed a considerable level of differentiation between extant and ancient populations at the same loci. Lateglacial and Holocene PAR values suggested that population size of the ancient population was small, in the range of 1/10 or 1/5 of the extant population. PAR analysis also detected two periods of rapid population growths (from ca. 11,100 and 3900 calibrated years before present (cal yr BP)) and three bottlenecks (around 9180, 7200 and 2200 cal yr BP), likely triggered by climatic change and human impact. Conclusion: Our results suggest that the paternal lineages observed today in the Retezat Mountains persisted at this site at least since the early Holocene. Combination of the results from the genetic and the PAR analyses furthermore suggests that the higher level of genetic variation found in the ancient populations and the loss of ancient allele types detected in the extant individuals were likely due to the repeated bottlenecks during the Holocene. This study demonstrates how past population size changes inferred from PAR records can be efficiently used in combination with ancient DNA studies. The joint application of palaeoecological and population genetic analyses proved to be a powerful tool to understand the influence of past population demographic changes on the haplotype diversity and genetic composition of forest tree species.
Snake bite is one of the most neglected public health issues in poor rural communities living in the tropics. Because of serious misreporting, the true worldwide burden of snake bite is not known. South Asia is the world's most heavily affected region, due to its high population density, widespread agricultural activities, numerous venomous snake species and lack of functional snake bite control programs. Despite increasing knowledge of snake venoms' composition and mode of action, good understanding of clinical features of envenoming and sufficient production of antivenom by Indian manufacturers, snake bite management remains unsatisfactory in this region. Field diagnostic tests for snake species identification do not exist and treatment mainly relies on the administration of antivenoms that do not cover all of the important venomous snakes of the region. Care-givers need better training and supervision, and national guidelines should be fed by evidence-based data generated by well-designed research studies. Poorly informed rural populations often apply inappropriate first-aid measures and vital time is lost before the victim is transported to a treatment centre, where cost of treatment can constitute an additional hurdle. The deficiency of snake bite management in South Asia is multi-causal and requires joint collaborative efforts from researchers, antivenom manufacturers, policy makers, public health authorities and international funders.
Background: The faunal and floral relationship of northward-drifting India with its neighboring continents is of general biogeographic interest as an important driver of regional biodiversity. However, direct biogeographic connectivity of India and Southeast Asia during the Cenozoic remains largely unexplored. We investigate timing, direction and mechanisms of faunal exchange between India and Southeast Asia, based on a molecular phylogeny, molecular clock-derived time estimates and biogeographic reconstructions of the Asian freshwater crab family Gecarcinucidae. Results: Although the Gecarcinucidae are not an element of an ancient Gondwana fauna, their subfamily Gecarcinucinae, and probably also the Liotelphusinae, evolved on the Indian Subcontinent and subsequently dispersed to Southeast Asia. Estimated by a model testing approach, this dispersal event took place during the Middle Eocene, and thus before the final collision of India and the Tibet-part of Eurasia. Conclusions: We postulate that the India and Southeast Asia were close enough for exchange of freshwater organisms during the Middle Eocene, before the final Indian--Eurasian collision. Our data support geological models that assume the Indian plate having tracked along Southeast Asia during its move northwards.