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Sperm morphometric in males of the paper wasp Polistes simillimus
(Alma Mater Studiorum, Univ Bologna, 2018-06-01)
Intraspecific variation in sperm morphometric is widespread across animal taxa and it might be related to different aspects of sexual selection. Within social insects, it has only been documented for some bee and ant ...
Sperm morphometric in males of the paper wasp polistes simillimus
(2018-01-01)
Intraspecific variation in sperm morphometric is widespread across animal taxa and it might be related to different aspects of sexual selection. Within social insects, it has only been documented for some bee and ant ...
Variability in sperm form and function in the context of sperm competition risk in two Tupinambis lizards
(Wiley, 2014-10)
In polyandrous species, sperm morphometry and sperm velocity are under strong sexual selection. Although several hypotheses have been proposed to explain the role of sperm competition in sperm trait variation, this aspect ...
Sperm competition and reproductive mode influence sperm dimensions and structure among snakes
(Wiley Blackwell Publishing, Inc, 2009-10)
The role of sperm competition in increasing sperm length is a controversial issue, because findings from different taxa seem contradictory. We present a comparative study of 25 species of snakes with different levels of ...
From storage to delivery: Sperm volume and number of spermatozoa inside storage organs and ejaculates in males of Timogenes elegans (Scorpiones: Bothriuridae)
(American Arachnological Society, 2018-08)
Sperm competition influences the evolution of many reproductive traits such as gonads, sperm or genitalia. Many sperm competition analyses concentrate in testes and ejaculates. Among arachnids, scorpions constitute an ...
Competitive males have higher quality sperm in a monogamous social bee
(BioMed Central, 2016)
Abstract
Background
Reproductive success is determined by the interplay between mating and fertilization success. In social insect species with male-biased sex ratios and ...
Ultrastructure of spermatozoa of orsolobidae (Haplogynae, Araneae) with implications on the evolution of sperm transfer forms in Dysderoidea
(Wiley, 2014-11)
Haplogynae are highly diverse with respect to the primary male genital system and sperm characteristics. Additionally, all sperm transfer forms (STF) known for spiders are present. Besides individually transferred sperm ...
The social organization of sperm whales in the Gulf of California and comparisons with other populations
(Journal of the Marine Biological Association of the United Kingdom, 2009)
Intra-specific variation in social organization provides valuable insights into the selective forces driving social evolution. Sperm whales are distributed globally and live far from shore, thus obtaining large sample sizes ...
Sexual Selection and the Evolution of Male Reproductive Traits in Benthic Octopuses
(Frontiers Media S.A., 2019-11)
Competition between same-sex organisms, or intra-sexual selection, can occur before and after mating, and include processes such as sperm competition and cryptic female choice. One of the consequences of intra-sexual ...
Diaphorocetus poucheti (Cetacea, Odontoceti, Physeteroidea) from Patagonia, Argentina: one of the earliest sperm whales
(Cambridge University Press, 2019-06)
Sperm whales (Physeteroidea) are the basal-most surviving lineage of odontocetes, represented today by just three highly specialized, deep-diving suction feeders. By contrast, extinct sperm whales were relatively diverse, ...