Traces of sex hormones extracted from a woolly mammoth's tusk provide the first direct evidence that adult males experienced musth, a testosterone-driven episode of heightened aggression against rival males, according to ...
Plants & Animals
May 3, 2023
0
119
During the rainy breeding season, the underwater "conversation" among electric fish changes. Fish revved up to make a match broadcast slightly different signals to advertise their presence and identify compatible mates.
Plants & Animals
Aug 10, 2023
0
57
A new analysis of old data suggests that the endangered erect-crested penguin's bizarre nesting habits—rejecting the first egg they lay—is because they can't feed two chicks, and the second, larger egg has a better chance ...
Plants & Animals
Oct 12, 2022
0
248
Proper development of the fetal penis requires not just testosterone from the testes, but a second hormone produced by other tissues, including the placenta, according to a new study publishing February 14 in the open-access ...
Plants & Animals
Feb 14, 2019
4
427
Among the first things that stand out about golden-collared manakins, a bird found in Panama and western Colombia, are the acrobatics of male adults during breeding season. Males also emit a particular call, the 'chee-poo', ...
Plants & Animals
Feb 6, 2019
0
82
Few of us would find a marriage proposal made amidst dirty dishes and messy clutter particularly romantic, but we are not the only creatures who realize that cleaning up your act may improve your chances of attracting a mate. ...
Plants & Animals
Sep 1, 2017
0
101
A pair of studies led by Indiana University researchers provide new evidence that when it comes to evolution, the testes may play a key role.
Evolution
Jun 15, 2016
0
19
Pre-birth exposure to high levels of the male sex hormone testosterone has already been shown to confer evolutionary advantages for men: strength of sex drive, sperm count, cardiovascular efficiency and spatial awareness, ...
Evolution
Apr 8, 2015
0
2030
For the male canary, the ability to sing a pitch-perfect song is critical to wooing female canaries. As the seasons change, so does song quality and frequency. The hormone testosterone plays a role in this changing song behavior.
Plants & Animals
Dec 30, 2013
0
0
For animals, prevailing in a fight affects their likelihood of winning future conflicts. The opposite is true of losing a fight. The sex hormone testosterone is often believed to mediate this "winner effect". Researchers ...
Plants & Animals
Apr 5, 2013
6
0
