Search results for "Viviparity"
showing 4 items of 4 documents
Scientific Reports
2019
Anthropogenic climate change ranks among the major global-scale threats to modern biodiversity. Extinction risks are known to increase via the interactions between rapid climatic alterations and environmentally-sensitive species traits that fail to adapt to those changes. Accumulating evidence reveals the influence of ecophysiological, ecological and phenological factors as drivers underlying demographic collapses that lead to population extinctions. However, the extent to which life-history traits influence population responses to climate change remains largely unexplored. The emerging 'cul-de-sac hypothesis' predicts that reptilian viviparity ('live-bearing' reproduction), a 'key innovati…
Hypoxia and hypothermia as rival agents of selection driving the evolution of viviparity in lizards
2017
[Aim]: The evolution of key innovations promotes adaptive radiations by opening access to new ecological opportunity. The acquisition of viviparity (live-bearing reproduction) has emerged as one such innovation explaining reptile proliferations into extreme climates. By evolving viviparity, females provide embryos with internally stable environments to complete development. The classical hypothesis suggests that natural selection for viviparity arises from low temperatures in cold climates, which promote prolonged egg retention in the mother's body. An alternative hypothesis proposes that declines in atmospheric oxygen at high elevations create natural selection for embryo retention to prov…
Data from: Life-history strategies indicate live-bearing in Nothosaurus (Sauropterygia)
2019
In Sauropterygia, a diverse group of Mesozoic marine reptiles, fossil evidence of viviparity (live‐bearing) only exists for Pachypleurosauria and Plesiosauria, and was assumed to also be the case for nothosaurs. Previous studies have successfully applied an extant squamate model to sauropterygian life‐history traits. In extant squamates, oviparity and viviparity are associated with differences in life‐history trait combinations. We establish growth curves for Nothosaurus specimens based on their humeral histology. We then analyse life‐history traits derived from these curves and compare inferred traits to those of modern squamates and pachypleurosaurs to assess their reproduction mode. We s…
Living on the edge: Meoneura obscurella in the ‘Wieliczka’ Salt Mine (southern Poland) exhibits the first case of lecithotrophic ovoviviparity in the…
2021
During the studies on the invertebrate fauna of the subterranean part of the “Wieliczka” Salt Mine in Wieliczka, Poland, the presence of many specimens of the dipteran species Meoneura obscurella (Fallén 1823) was observed. Organic remains and faeces related to the presence of mice (Mus musculus) were indicated as a potential food source for the insects. M. obscurella displays lecithotrophic viviparity (ovoviviparity), which has developed due to extremely harsh abiotic conditions and a lack of food. This is the first documented case of lecithotrophic viviparity within the fly family Carnidae. Based on the ability of this species to inhabit and reproduce in the conditions of the subterranean…