Male and female black widow spiders exhibit striking sexual dimorphism. Females are significantly larger, darker, and possess the iconic red hourglass ...

The coronavirus disease 2019 (COVID-19) outbreak caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was declared to be a global pandemic by the World Health Organization (WHO) on ...

In mosquitofish, of the genus Gambusia, male fish are smaller than females -- sometimes only half the size. Biologists had previously assumed that smaller male mosquitofish had at least some ...

If you liked this story, share it with other people. Successful conservation interventions have helped mountain gorilla populations recover from 620 in 1989 to more than 1,000 today. However, mountain ...

Many aquatic animals exhibit sequential hermaphroditism, changing sex to adapt to environmental cues, social dominance, or ...

A Vermont elementary school is reportedly removing "male" and "female" language from its fifth grade science lessons covering the human body, puberty and reproduction. In a letter sent home to parents ...

Intersex is an umbrella term for people who are born with one or more traits in their chromosomes, genitals, hormones, or internal reproductive organs that don’t fit the typical male or female ...

A Vermont elementary school says it will no longer use the words “male” or “female” when teaching fifth-grade students about puberty and human reproductive systems. Families of students at Founders ...