scholarly journals Motivating conservation even for widespread species using genetic uniqueness and relational values

2022 ◽  
Vol 266 ◽  
pp. 109438
Author(s):  
Harold N. Eyster ◽  
Paige Olmsted ◽  
Robin Naidoo ◽  
Kai M.A. Chan
2018 ◽  
Author(s):  
David Thomas Mellor ◽  
Catherine Tarsiewicz ◽  
Rebecca Jordan

Females of a widespread species of the rock‐dwelling haplochromine cichlids of Lake Malawi, Maylandia zebra, show preference for males that successfully evict intruding males from their territory. This behaviour, experimentally induced by the investigators in a laboratory setting, was also preferred over males that were not permitted to interact with any other individual.


2017 ◽  
Vol 51 ◽  
pp. 242-250
Author(s):  
M. V. Dulin

Tetralophozia setiformis is a widespread species occurring usually without organs of sexual and asexual reproduction. Gemmae of Tetralophozia setiformis were observed for the second time in Russia and Eurasia in the Northern Urals, Komi Republic. They form compact masses over upper leaves. The compact masses consist largely (70 %) of immature gemmae. Description of gemmae and gemmiparous shoots from the Northern Urals and their comparison with those from the other known localities, namely British Columbia (Canada) and the Murmansk Region (European Russia) were carried out. The gemmiparous plants of T. setiformis from the Northern Urals have approximately the same width as plants without gemmae but they are shorter. The leaves of gemmiparous plants from the Northern Urals are similar to leaves of gemmiparous plants from British Columbia. The leaf shape in upper part of the gemmiparous shoots varies from the typical to ± modified from gemmae production. These leaf shape transitions include reduction of leaf size and lobe number from 4 to 2–3, suppression of development and disappearance of characteristic teeth at the base of sinus. Gemmae size (17 × 22 μm) of plants from the Northern Urals is within variability recorded for plants from the Murmansk Region and British Columbia.


Genetics ◽  
2003 ◽  
Vol 163 (1) ◽  
pp. 147-157 ◽  
Author(s):  
Arjun Sivasundar ◽  
Jody Hey

AbstractCaenorhabditis elegans has become one of the most widely used model research organisms, yet we have little information on evolutionary processes and recent evolutionary history of this widespread species. We examined patterns of variation at 20 microsatellite loci in a sample of 23 natural isolates of C. elegans from various parts of the world. One-half of the loci were monomorphic among all strains, and overall genetic variation at microsatellite loci was low, relative to most other species. Some population structure was detected, but there was no association between the genetic and geographic distances among different natural isolates. Thus, despite the nearly worldwide occurrence of C. elegans, little evidence was found for local adaptation in strains derived from different parts of the world. The low levels of genetic variation within and among populations suggest that recent colonization and population expansion might have occurred. However, the patterns of variation are not consistent with population expansion. A possible explanation for the observed patterns is the action of background selection to reduce polymorphism, coupled with ongoing gene flow among populations worldwide.


Zootaxa ◽  
2018 ◽  
Vol 4379 (1) ◽  
pp. 47 ◽  
Author(s):  
JACK M. CRAIG ◽  
LUIZ R. MALABARBA ◽  
WILLIAM G. R. CRAMPTON ◽  
JAMES S. ALBERT

Banded Knifefishes (Gymnotus, Gymnotidae) comprise the most species-rich, ecologically tolerant (eurytopic), and geographically widespread genus of Neotropical electric fishes (Gymnotiformes), with 40 valid species occupying most habitats and regions throughout the humid Neotropics. Despite substantial alpha-taxonomic work in recent years, parts of the genus remain characterized by taxonomic confusion. Here we describe and delimit species of the G. carapo and G. tigre clades from the southern Neotropics, using body proportions (caliper-based morphometrics), fin-ray, scale and laterosensory-pore counts (meristics), quantitative shape differences (geometric morphometrics), osteology, color patterns and electric organ discharges. We report these data from 174 Gymnotus specimens collected from 100 localities throughout the southern Neotropics, and delimit species boundaries in a multivariate statistical framework. We find six species of the G. carapo clade (G. carapo australis, G. cuia n. sp., G. chimarrao, G. omarorum, G. pantanal, and G. sylvius), and two species of the G. tigre clade (G. inaequilabiatus and G. paraguensis) in the southern Neotropics. The new species G. cuia is readily distinguished from the morphologically similar and broadly sympatric G. c. australis by a shorter head and deeper head and body, and from the morphologically similar and sympatric G. omarorum by fewer lateral-line ventral rami and fewer pored lateral-line scales anterior to the first ventral ramus. We also review the geographic distributions of all eight species of the G. carapo and G. tigre clades in the southern Neotropics, showing that G. cuia is the most widespread species in the region. These results affirm the importance of understanding the structure of variation within and between species, both geographic and ontogenetic, in delimiting species boundaries. 


2021 ◽  
Author(s):  
Corinne Y. Bataille ◽  
Sanna K. Malinen ◽  
Johanna Yletyinen ◽  
Nigel Scott ◽  
Philip O'B. Lyver

BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Hong-Yan Zhao ◽  
Lin Wen ◽  
Yu-Feng Miao ◽  
Yu Du ◽  
Yan Sun ◽  
...  

Abstract Background A comprehensive evaluation of the -omic profiles of venom is important for understanding the potential function and evolution of snake venom. Here, we conducted an integrated multi-omics-analysis to unveil the venom-transcriptomic and venomic profiles in a same group of spine-bellied sea snakes (Hydrophis curtus) from the South China Sea, where the snake is a widespread species and might generate regionally-specific venom potentially harmful to human activities. The capacity of two heterologous antivenoms to immunocapture the H. curtus venom was determined for an in-depth evaluation of their rationality in treatment of H. curtus envenomation. In addition, a phylogenetic analysis by maximum likelihood was used to detect the adaptive molecular evolution of full-length toxin-coding unigenes. Results A total of 90,909,384 pairs of clean reads were generated via Illumina sequencing from a pooled cDNA library of six specimens, and yielding 148,121 unigenes through de novo assembly. Sequence similarity searching harvested 63,845 valid annotations, including 63,789 non-toxin-coding and 56 toxin-coding unigenes belonging to 22 protein families. Three protein families, three-finger toxins (3-FTx), phospholipase A2 (PLA2), and cysteine-rich secretory protein, were detected in the venom proteome. 3-FTx (27.15% in the transcriptome/41.94% in the proteome) and PLA2 (59.71%/49.36%) were identified as the most abundant families in the venom-gland transcriptome and venom proteome. In addition, 24 unigenes from 11 protein families were shown to have experienced positive selection in their evolutionary history, whereas four were relatively conserved throughout evolution. Commercial Naja atra antivenom exhibited a stronger capacity than Bungarus multicinctus antivenom to immunocapture H. curtus venom components, especially short neurotoxins, with the capacity of both antivenoms to immunocapture short neurotoxins being weaker than that for PLA2s. Conclusions Our study clarified the venom-gland transcriptomic and venomic profiles along with the within-group divergence of a H. curtus population from the South China Sea. Adaptive evolution of most venom components driven by natural selection appeared to occur rapidly during evolutionary history. Notably, the utility of commercial N. atra and B. multicinctus antivenoms against H. curtus toxins was not comprehensive; thus, the development of species-specific antivenom is urgently needed.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Belinda van Heerwaarden ◽  
Carla M. Sgrò

AbstractForecasting which species/ecosystems are most vulnerable to climate warming is essential to guide conservation strategies to minimize extinction. Tropical/mid-latitude species are predicted to be most at risk as they live close to their upper critical thermal limits (CTLs). However, these assessments assume that upper CTL estimates, such as CTmax, are accurate predictors of vulnerability and ignore the potential for evolution to ameliorate temperature increases. Here, we use experimental evolution to assess extinction risk and adaptation in tropical and widespread Drosophila species. We find tropical species succumb to extinction before widespread species. Male fertility thermal limits, which are much lower than CTmax, are better predictors of species’ current distributions and extinction in the laboratory. We find little evidence of adaptive responses to warming in any species. These results suggest that species are living closer to their upper thermal limits than currently presumed and evolution/plasticity are unlikely to rescue populations from extinction.


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