In most animals, body size shrinks when food becomes scarce, but some parts are protected from shrinkage. In humans without enough food, the body becomes small, but the size of the head stays the same, hinting at biological ...
Plants & Animals
May 16, 2019
0
55
Two Hawaiian crows, or alala, have done something momentous in the struggle to save the critically endangered species.
Ecology
May 15, 2019
0
4
When it comes to choosing a mate, female guppies often go for the mates with the flashiest, most interesting color patterns.
Plants & Animals
May 15, 2019
1
123
Having a sexually transmitted infection and passing it on to a mate could benefit male animals, research from The Australian National University (ANU) has found.
Plants & Animals
May 14, 2019
2
128
Female presidents have less power to shape policy and are held to higher standards in key policy areas than male presidents, according to a study led by a Georgia State political science researcher.
Social Sciences
May 01, 2019
0
4
Programming children watch on American TV shows systematic gender inequality, according to new research co-authored by Dafna Lemish of the School of Communication and Information at Rutgers University-New Brunswick.
Social Sciences
Apr 30, 2019
0
11
In an African forest where leopards and poisonous mamba dwell, a University of Oregon team once had to flee charging boar. But it was a brief detour in research that adds to the idea that bonobos are neither hippies nor vegans.
Plants & Animals
Apr 30, 2019
0
65
Though less likely to study in a formal technology or engineering course, America's girls are showing more mastery of those subjects than their boy classmates, according to newly released national education data.
Education
Apr 30, 2019
2
14
Male prisoners are much more likely than men in the wider population to have suffered childhood adversities such as child maltreatment or living in a home with domestic violence, according to a new report by Public Health ...
Social Sciences
Apr 29, 2019
0
327
When the NFL draft takes place, it will represent a professional dream come true for the 224 college football players who get picked.
Social Sciences
Apr 26, 2019
0
5
Male (♂) refers to the sex of an organism, or part of an organism, which produces small mobile gametes, called spermatozoa. Each spermatozoon can fuse with a larger female gamete or ovum, in the process of fertilization. A male cannot reproduce sexually without access to at least one ovum from a female, but some organisms can reproduce both sexually and asexually.
Not all species share a common sex-determination system. In humans and most animals, sex is determined genetically but in other species it can be determined due to social, environmental, or other factors. The existence of two sexes seems to have been selected independently across different evolutionary lineages (see Convergent Evolution). Accordingly, sex is defined operationally across species by the type of gametes produced (ie: spermatozoa vs. ova) and differences between males and females in one lineage are not always predictive of differences in another.
Male/Female dimorphism between organisms or reproductive organs of different sexes is not limited to animals; male gametes are produced by chytrids, diatoms and land plants, among others. In land plants, female and male designate not only the female and male gamete-producing organisms and structures but also the structures of the sporophytes that give rise to male and female plants.
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