Results 11 to 20 of about 2,992 (213)
Drivers of diversification in sharks and rays (Chondrichthyes: Elasmobranchii) [PDF]
Frontiers in Ecology and EvolutionElasmobranchs (sharks and rays) are a charismatic lineage of unquestionable ecological importance in past and present marine ecosystems. Represented by over 1200 species, elasmobranchs have undergone substantial shifts in taxonomic diversity since their ...
Patrick L. Jambura
exaly +7 more sources
The ancient and helical architecture of Elasmobranchii’s spermatozoa enables progressive motility in viscous environments [PDF]
PLoS ONESubclass Elasmobranchii belongs to an old evolutionary class of Chondrichthyes that diverged 450 mya, presenting a wide diversity of reproductive strategies while preserving the ancient mode of internal fertilization.
Juan F. Asturiano +2 more
exaly +3 more sources
No evidence for population-level benefits of polyandry in sharks and rays. [PDF]
PLoS ONEMating system variation refers to the spectrum between genetic monogamy and polyandry, and has important consequences for sexual conflict, sexual selection and individual fitness in animals.
Joel H Gayford +1 more
doaj +2 more sources
, 2021 Subclass ELASMOBRANCHII Bonaparte, 1838 REMARKS Fossils were only collected by surface picking around the archaeocete whale carcasses (protocetids and basilosaurids, see Gingerich & Zouhri 2015), and thus the majority of small to medium-sized sharks and rays remain currently unknown.Thousands of specimens were collected from several localities ...
Zouhri, Samir +9 more
openaire +3 more sources
Evolutionary trends in the elasmobranch neurocranium [PDF]
Scientific ReportsThe neurocranium (braincase) is one of the defining vertebrate characters. Housing the brain and other key sensory organs, articulating with the jaws and contributing to the shape of the anteriormost portion of the body, the braincase is undoubtedly of ...
Joel H. Gayford +2 more
doaj +2 more sources
The mitogenomic phylogeny of the Elasmobranchii (Chondrichthyes)
Mitochondrial DNA Part A, 2017 Here we present a mitogenomic perspective on the evolution of sharks and rays, being a first glance on the complete mitochondrial history of such an old and diversified group of vertebrates. The Elasmobranchii is a diverse subclass of Chondrichthyes, or cartilaginous fish, with about 1200 species of ocean- and freshwater-dwelling fishes spread all over
Amaral, Cesar R. L. +4 more
openaire +4 more sources
Selachian faunas from the earliest Cretaceous Purbeck Group of Dorset, southern England. [PDF]
, 2002 Abundant selachian remains have been recovered from a number of horizons through the Purbeck Group at Durlston Bay, Lulworth Cove and Stair Hole in southern England.
Rees, J., Underwood, Charlie J.
core +7 more sources
Occurrence of multiple congenital anomalies in Potamotrygon amandae (Elasmobranchii, Potamotrygoninae) embryos, including the first report of bicephaly. [PDF]
J Fish BiolAbstract Reports of teratogenic embryos in elasmobranchs have been documented in multiple species, with proposed aetiologies including environmental disturbances, genetic mutations, predation, exposure to endocrine‐disrupting compounds and maternal stress.
de Castro Ribeiro D +2 more
europepmc +2 more sources
Sexual Size Dimorphism in Rays and Skates (Elasmobranchii: Batoidea). [PDF]
Ecol EvolABSTRACT Sexual size dimorphism (SSD) is a widely observed but poorly understood phenomenon in which male and female animals differ in body size (e.g., length or mass). Despite extensive research on the interspecific distribution of SSD across various lineages, the evolutionary drivers behind male‐biased and female‐biased SSD remain ...
Gayford JH +4 more
europepmc +4 more sources
Frontiers in Conservation Science, 2022 Monitoring population size and dynamics of threatened or low-density species is often both logistically difficult and costly. Recently, social media has emerged as a new tool for species monitoring.
Julia Saltzman +8 more
doaj +1 more source