0000000000131882
AUTHOR
Helmut Hemmer
showing 12 related works from this author
Hybridization within the Rana ridibunda Complex of North Africa
1980
Abstract Cellogel electrophoretic study of the plasma protein pattern, especially the albumin fractions, and microdensitometric determination of erythrocyte nuclear DNA amount in 25 frogs of the Rana ridibunda complex from different localities in Morocco and Algeria allows the conclusion that two different forms of this complex are hybridizing in North Africa, as it is found in the Rana esculenta complex in Europe or in the East Asian green frogs. These forms can be identified by their albumin alleles, but not yet by their morphology. They produce mainly triploid hybrids.
Zur Bedeutung des Geruchssinnes beim Nahrungserwerb von Kröten (Amphibia, Anura, Bufonidae): Versuche mit der Kreuzkröte (Bufo calamita Laur.)
1975
The influence of olfactory and visual prey stimuli on the feeding behaviour of toads was studied as well as their response to lasting olfactory cues. A further aim was to find simple methods for testing olfactory responsiveness in anurans. Subjects were 8 adult specimens of the European species Bufo calamita (natterjack) kept in captivity one year at least. The results point to the role of olfaction in these animals.
Molecular Evolution and the Phylogenetic Relationships of the African Toad, Bufo danielae PERRET, 1977 (Salientia : Bufonidae)
1980
Abstract Phylogenetic relationships of the African toad Bufo danielae are investigated using a variety of biochemical approaches. Nuclear DNA content was assayed and compared to representatives of three species groups of African Bufo. Cellogel electrophoresis of plasma proteins was performed and patterns of B. danielae compared with those of representatives of the African B. regularis species complex. Finally microcomplement fixation analyses of albumin relationships of B. danielae and African Bufo were carried out. The strengths of the varied approaches for phylogenetic analysis are discussed. B. danielae appears most closely related to B. maculatus and B. pusillus, it being some 5-6 mill…
conservation Sand cats and zoos.
1976
The Jaguar - Panthera onca gombaszoegensis (Kretzoi, 1938) (Carnivora: Felidae) in the late lower pleistocene of Akhalkalaki (south Georgia; Transcau…
2001
Abstract A lower hemimandibula of a pantherine cat of Akhalkalaki (south Georgia, Transcaucasia) is re-examinated. The fossil originates from lacustrine sediments of late Lower Pleistocene age (0.9 − 0.8 Ma B.P.) above the Jaramillo polarity subzone. A tooth-by-tooth analysis comparing the fossil with Lower and Middle Pleistocene lions, tigers and jaguars and Holocene southwest Asian lions assigns it to the Eurasian jaguar, Panthera onca gombaszoegensis. Palaeoenvironmental reconstruction indicates a dry, warm meadow-steppe influenced by montane condition, with permanent water bodies present. This is consistent with the strong open-water affinities of the modern jaguar. The morphological pr…
Die evolution der pantherkatzen modell zur überprüfung der brauchbarkeit der hennigschen prinzipien der phylogenetischen systematik für wirbeltierpal…
1981
Die Arten- und Gattungsgruppe der Pantherkatzen (Panthera, Uncia, Neofelis) ist zoologisch, palaontologisch und biogeographisch soweit studiert, das ein zwar noch viele Lucken enthaltendes, aber in sich einheitliches und widerspruchsfreies Bild ihrer Evolutionsablaufe moglich ist. Damit eignet sie sich als Modell zur Uberprufung der Anwendbarkeit der HENNiGschen Prinzipien der phylogenetischen Systematik auf rein wirbeltierpalaontologische Untersuchungen. Hierbei zeigt es sich, das die Anwendung dieser Methoden infolge begrifflicher Klarheit zwar von unbestreitbarem Nutzen ist, allein fur die Rekonstruktion evolutiver Ablaufe jedoch nicht ausreicht. Dichotomie oder Radiation kann keine prin…
Breeding Geoffroy's cat in captivity
1975
Molecular phylogeny of the extinct cave lion Panthera leo spelaea.
2004
To reconstruct the phylogenetic position of the extinct cave lion (Panthera leo spelaea), we sequenced 1 kb of the mitochondrial cytochrome b gene from two Pleistocene cave lion DNA samples (47 and 32 ky B.P.). Phylogenetic analysis shows that the ancient sequences form a clade that is most closely related to the extant lions from Africa and Asia; at the same time, cave lions appear to be highly distinct from their living relatives. Our data show that these cave lion sequences represent lineages that were isolated from lions in Africa and Asia since their dispersal over Europe about 600 ky B.P., as they are not found among our sample of extant populations. The cave lion lineages presented h…
Local adaptation, coadaptation, and population boundaries
1986
Coadaptation can occur either because of local adaptation in a geographically widespread population and/or because of intrinsic adaptation to the state of other genes or chomosomes. In either event, hybridization between animals with differently coadapted gene or chromosomal complexes can result in a decrease in fertility, viability, etc. in the initial hybrids and especially in later generations. This is known as an outbreeding depression. Moreover, releasing animals not adapted to the local environment can seriously hamper the effectiveness of a reintroduction program, and hybridization can also destroy the local adaptation. Coadapted gene complexes are best detected through studies on na…
The Balearic toad (Bufo viridis balearicus (BOETTGER, 1881)), human bronze age culture, and Mediterranean biogeography
1981
Abstract Microcomplement fixation analysis of albumin relationship shows that the Balearic green toad (Bufo viridis balearicus) is not an original, autochthonous member of the basically Miocene fauna of these western Mediterranean islands, but a quite recent newcomer. The plasma protein pattern clearly points to its close populational relationship to the Tyrrhenian islands' conspecifics. The male and female release vocalization shows the same, and this is in accordance with the external morphology too. There has been no possibility for toads to reach the Balearic Islands in Pleistocene or Holocene via land bridges, nor are they candidates for any sea drifting. Anthropogenic introduction mu…
Tracking Five Millennia of Horse Management with Extensive Ancient Genome Time Series
2019
Summary Horse domestication revolutionized warfare and accelerated travel, trade, and the geographic expansion of languages. Here, we present the largest DNA time series for a non-human organism to date, including genome-scale data from 149 ancient animals and 129 ancient genomes (≥1-fold coverage), 87 of which are new. This extensive dataset allows us to assess the modern legacy of past equestrian civilizations. We find that two extinct horse lineages existed during early domestication, one at the far western (Iberia) and the other at the far eastern range (Siberia) of Eurasia. None of these contributed significantly to modern diversity. We show that the influence of Persian-related horse …