Time filter

Source Type

Hannover, Germany

Biodiversity hotspots have been in the mainstream of studies and debates regarding conservation and biodiversity. Results, however, are skewed towards vertebrates and the tropics, and cannot simply be generalized to invertebrates and temperate biodiversity hotspot regions. In this first study of its kind, we explored the spatial patterns of Larentiinae moth (except genus Eupithecia Curtis, 1825) species richness and beta diversity in two neighbouring temperate biodiversity hotspots, the Caucasus and the Irano-Anatolian biodiversity hotspots, Middle Palearctic. We explored how spatial gradients contribute to the formation of moth species richness in these two biodiversity hotspots by disentangling beta diversity patterns to spatial turnover and nestedness components. Larentiinae moths showed a positive association with latitude and a unimodal relationship with elevation. The latitudinal gradient contributed more than the elevational gradient in formation of biodiversity. Both hotspots showed similar patterns of beta diversity partitioning, demonstrating a large contribution of spatial turnover to biodiversity formation. Constant high values of spatial turnover across 17° of latitudinal gradient may indicate that diversity has been formed by a consistent mechanism of horizontal species level diversification of larentine moths throughout mountains. © 2015, Springer International Publishing Switzerland. Source

Schierwater B.,ITZ
Advances in Experimental Medicine and Biology | Year: 2010

For more than a century the origin of metazoan animals and for less than three years the early evolution of Hox genes has been debated. Both discussions are intrinsically tied together. New data from whole genome sequencing and recent progress in phylogeny of basal metazoans allow to provide an answer. The evolution of diploblastic animals (Placozoa, Porifera, Ctenophora and Cnidaria) and Bilateria (all higher animals) went parallel. The early split of these two lineages led to the evolution of a Hox system in Bilateria and the presence of Hox-like genes in Cnidaria and Placozoa. © 2010 Landes Bioscience and Springer Science+Business Media. Source

Damm S.,ITZ | Dijkstra K.-D.B.,National Museum of Natural History Naturalis | Hadrys H.,ITZ | Hadrys H.,Yale University
Molecular Phylogenetics and Evolution | Year: 2010

In the last few million years, tropical Africa has experienced pronounced climatic shifts with progressive aridification. Such changes must have had a great impact on freshwater biota, such as Odonata. With about forty species, Trithemis dominates dragonfly communities across Africa, from rain-pools to streams, deserts to rainforests, and lowlands to highlands. Red-bodied species tend to favor exposed, standing and often temporary waters, have strong dispersal capacities, and some of the largest geographic ranges in the genus. Those in cooler habitats, like forest streams, are generally dark-bodied and more sedentary. We combined molecular analyses of ND1, 16S, and ITS (ITSI, 5.8S, and ITSII) with morphological, ecological, and geographical data for 81% of known Trithemis species, including three Asian and two Madagascan endemics. Using molecular clock analyses, the genus's origin was estimated 6-9 Mya, with multiple lineages arising suddenly around 4 Mya. Open stagnant habitats were inferred to be ancestral and the rise of Trithemis may have coincided with savannah-expansion in the late Miocene. The adaptation of red species to more ephemeral conditions leads to large ranges and limited radiation within those lineages. By contrast, three clades of dark species radiated in the Plio-Pleistocene, each within distinct ecological confines: (1) lowland streams, (2) highland streams, and (3) swampy habitats on alternating sides of the Congo-Zambezi watershed divide; together giving rise to the majority of species diversity in the genus. During Trithemis evolution, multiple shifts from open to more forested habitats and from standing to running waters occurred. Allopatry by habitat fragmentation may be the dominant force in speciation, but possibly genetic divergence across habitat gradients was also involved. The study demonstrates the importance of combining ecological and phylogenetic data to understand the origin of biological diversity under great environmental change. © 2009 Elsevier Inc. All rights reserved. Source

Osigus H.-J.,ITZ | Eitel M.,ITZ | Eitel M.,University of Hong Kong | Schierwater B.,ITZ | And 2 more authors.
Molecular Phylogenetics and Evolution | Year: 2013

The ever-lingering question: "What did the urmetazoan look like?" has not lost its charm, appeal or elusiveness for one and a half centuries. A solid amount of organismal data give what some feel is a clear answer (e.g. Placozoa are at the base of the metazoan tree of life (ToL)), but a diversity of modern molecular data gives almost as many answers as there are exemplars, and even the largest molecular data sets could not solve the question and sometimes even suggest obvious zoological nonsense. Since the problems involved in this phylogenetic conundrum encompass a wide array of analytical freedom and uncertainty it seems questionable whether a further increase in molecular data (quantity) can solve this classical deep phylogeny problem. This review thus strikes a blow for evaluating quality data (including morphological, molecule morphologies, gene arrangement, and gene loss versus gene gain data) in an appropriate manner. © 2012 Elsevier Inc. Source

Damm S.,ITZ | Schierwater B.,ITZ | Schierwater B.,American Museum of Natural History | Hadrys H.,ITZ | Hadrys H.,Yale University
Molecular Ecology | Year: 2010

Modern taxonomy requires an analytical approach incorporating all lines of evidence into decision-making. Such an approach can enhance both species identification and species discovery. The character-based DNA barcode method provides a molecular data set that can be incorporated into classical taxonomic data such that the discovery of new species can be made in an analytical framework that includes multiple sources of data. We here illustrate such a corroborative framework in a dragonfly model system that permits the discovery of two new, but visually cryptic species. In the African dragonfly genus Trithemis three distinct genetic clusters can be detected which could not be identified by using classical taxonomic characters. In order to test the hypothesis of two new species, DNA-barcodes from different sequence markers (ND1 and COI) were combined with morphological, ecological and biogeographic data sets. Phylogenetic analyses and incorporation of all data sets into a scheme called taxonomic circle highly supports the hypothesis of two new species. Our case study suggests an analytical approach to modern taxonomy that integrates data sets from different disciplines, thereby increasing the ease and reliability of both species discovery and species assignment. © 2010 Blackwell Publishing Ltd. Source

Discover hidden collaborations