Results 51 to 60 of about 67,643 (303)

Sperm removal during copulation confirmed in the oldest extant damselfly, Hemiphlebia mirabilis [PDF]

PeerJ, 2016
Postcopulatory sexual selection may favour mechanisms to reduce sperm competition, like physical sperm removal by males. To investigate the origin of sperm removal, I studied the reproductive behaviour and mechanisms of sperm competition in the only ...
Adolfo Cordero-Rivera
doaj   +2 more sources

A Surface‐engineered Microfluidic Device for Antibody‐Mediated Negative Selection of High‐Quality Sperm for Assisted Reproduction

Advanced Functional Materials, EarlyView.
This study reports a microfluidic device with a functionalized surface utilizing a polyoxazoline coating and covalently immobilized gold nanoparticles and anti‐phosphatidylserine antibody. The device efficiently eliminates pre‐apoptotic and apoptotic spermatozoa and yields sperm with substantially improved quality and low DNA damage, offering a simple ...
Soraya Rasi Ghaemi, David J. Sharkey, Nicole O. McPherson, Markos Negash Alemie, Krasimir Vasilev, Sarah A. Robertson   +5 more
wiley   +1 more source

The bold and the sperm: positive association between boldness and sperm number in the guppy [PDF]

Royal Society Open Science, 2019
Assessing the consequences of personality traits on reproductive success is one of the most important challenges in personality studies and critical to understand the evolutionary implications of behavioural variability among animals.
Clelia Gasparini, Elizabeth M. Speechley, Giovanni Polverino   +2 more
doaj   +1 more source

The dynamics of sperm cooperation in a competitive environment [PDF]

, 2014
Sperm cooperation has evolved in a variety of taxa and is often considered a response to sperm competition, yet the benefit of this form of collective movement remains unclear.
Fisher, Heidi S., Giomi, Luca, Hoekstra, Hopi E., Mahadevan, L.   +3 more
core   +1 more source

Nanodiamond Quantum Sensors for Probing Free Radical Biology

Advanced Functional Materials, EarlyView.
Free radicals play key roles in cellular signaling and disease but remain difficult to measure in living systems. Nanodiamonds (NDs) with nitrogen‐vacancy (NV) centers enable quantum sensing of local magnetic noise via T₁ relaxometry, providing nondestructive radical detection in living cells.
Qi Lu, Yingke Wu, Tanja Weil
wiley   +1 more source

Experimental evolution reveals that sperm competition intensity selects for longer, more costly sperm [PDF]

, 2017
It is the differences between sperm and eggs that fundamentally underpin the differences between the sexes within reproduction. For males, it is theorized that widespread sperm competition leads to selection for investment in sperm numbers, achieved by ...
Godwin, Joanne L., Vasudeva, Ramakrishnan, Michalczyk, Lukasz, Martin, Oliver Y., Lumley, Alyson J., Chapman, Tracey, Gage, Matthew J. G.   +6 more
core   +4 more sources

Audience effects in the Atlantic molly (Poecilia mexicana)–prudent male mate choice in response to perceived sperm competition risk?

Frontiers in Zoology, 2009
Background Multidirectional interactions in social networks can have a profound effect on mate choice behavior; e.g., Poecilia mexicana males show weaker expression of mating preferences when being observed by a rival. This may be an adaptation to reduce
Kronmarck Claudia, Hennige-Schulz Carmen, Mahlow Kristin, Ziege Madlen, Tiedemann Ralph, Streit Bruno, Plath Martin   +6 more
doaj   +1 more source

Cannibalism and protective behavior of eggs in Arctic charr (Salvelinus alpinus)

Ecology and Evolution, 2021
From video recordings of spawning events, we quantified protective and cannibalistic behavior of Arctic charr occurring immediately after spawning. The number of fish cannibalizing on stray eggs was examined regarding (a) whether more than one male shed ...
Marilena Frye, Torvald B. Egeland, Jarle Tryti Nordeide, Ivar Folstad   +3 more
doaj   +1 more source

Sperm competition-induced plasticity in the speed of spermatogenesis [PDF]

, 2004
Background: Sperm competition between rival ejaculates over the fertilization of ova typically selects for the production of large numbers of sperm.
Athina Giannakara, Lukas Schärer, Steven A. Ramm, GA Parker, GA Parker, GA Parker, J Lehtonen, GA Parker, L Schärer, PG Byrne, CD Soulsbury, DJ Hosken, LW Simmons, LW Simmons, RR Warner, SA Ramm, SA Ramm, S Lüpold, S Lüpold, SA Ramm, M Rowe, A Oppliger, L Schärer, SA Ramm, RC Firman, A Bjork, EJ Peirce, P Ladurner, L Schärer, L Schärer, T Janicke, T Janicke, L Schärer, EL Charnov, Y Clermont, T Janicke, R Arbore, K Sekii, R Billard, ML Meistrich, PM Kluin, VS Brauer, L Marie-Orleach   +42 more
core   +3 more sources

Chronic Hypoxia Disrupts Spermatogenesis Through ASXL2–EZH2–Mediated Microtubule Destabilization

Advanced Science, EarlyView.
This study reveals the mechanism by which chronic hypoxia impairs spermatogenesis via the ASXL2–EZH2 axis, hindering the transition of spermatids from round to elongated forms. Key findings reveal that under hypoxic conditions, downregulated ASXL2 expression reduces EZH2 binding to the CEP162 promoter, leading to decreased H3K27me3 modification and ...
Jun Yin, Mengjie Zhang, Wenying Liu, Wenlong Shen, Debao Li, Hongming Miao, Fang Deng, Gang Zhang, Yi Tian, Yi Zhang, Zhihu Zhao, Bing Ni   +11 more
wiley   +1 more source