illustration of purple mitochondrion within a cell
Rogue Mitochondria Turn Hermaphroditic Snails Female: Study
The accidental finding marks the first time a phenomenon called cytoplasmic sterility, known to occur in plants, has been found in animals.
ABOVE: © ISTOCK.COM, Christoph Burgstedt
Rogue Mitochondria Turn Hermaphroditic Snails Female: Study
Rogue Mitochondria Turn Hermaphroditic Snails Female: Study

The accidental finding marks the first time a phenomenon called cytoplasmic sterility, known to occur in plants, has been found in animals.

The accidental finding marks the first time a phenomenon called cytoplasmic sterility, known to occur in plants, has been found in animals.

ABOVE: © ISTOCK.COM, Christoph Burgstedt

sex

Two bonobos facing each other on a tree branch
Q&A: In Battle of the Sexes, Dominance Doesn’t Always Equal Power
Raegan Scharfetter | May 18, 2022
The Scientist spoke to hyena researcher Eve Davidian for a broad look at power relationships between male and female mammals.
mixing blue and pink smoke, symbolic of the muddled boundaries between sexes
Opinion: Biological Science Rejects the Sex Binary, and That’s Good for Humanity
Agustín Fuentes | May 12, 2022
Evidence from various sciences reveals that there are diverse ways of being male, female, or both. An anthropologist argues that embracing these truths will help humans flourish.
Reddish shelf fungi on a log
This Fungus Has More Than 17,000 Sexes
James M. Gaines | Apr 20, 2022
Advances in sequencing technologies have finally allowed researchers to zero in on the genetic diversity underlying the incredible mating system of shelf fungi.
a microscope image of a rotifer
Bacterial Enzyme Keeps Rotifers’ Transposable Elements in Check
Christie Wilcox | Mar 3, 2022
Jumping genes in bdelloid rotifers are tamped down by DNA methylation performed by an enzyme pilfered from bacteria roughly 60 million years ago, a study finds.
illustration of people of different genders and races
Does Biological Sex Influence COVID-19 Outcomes?
Annie Melchor | Nov 2, 2021
It’s unclear whether differing odds of dying between men and women reflect inherent differences between male and female immune systems or differences rooted in gender norms.
Rhino upside down, in the sky
2021 Ig Nobel Prizes Honor Decongestant Orgasms, Rhino Transport
Lisa Winter | Sep 14, 2021
A full beard can absorb nearly 40 percent of the shock from a punch to the face, according to one winning study.
A grayscale electron micrograph shows hundreds of sperm cells stuck together in the foreground
Antibodies Stop Sperm in Their Tracks
Abby Olena | Aug 11, 2021
Engineered antibodies trap and immobilize human sperm in the reproductive tract of female sheep, paving the way for possible use as a nonhormonal contraceptive in people.
a pair of Northern Cardinals perched on a tree branch
Females Gain Ground as Biomedical Research Subjects
Shawna Williams | Jun 9, 2020
A study finds improvement in the proportion of scientific projects that include both sexes, but analyzing results by sex is not routine.
fruit fly drosophila melanogaster sperm sex peptide memory reproduction
Sex Promotes Lasting Memories in Female Flies
Ruth Williams | Nov 20, 2019
A protein present in the ejaculate of male fruit flies activates long-term memory formation in the brains of their female partners.
same sex sexual behavior homosexual heterosexual genetics gwas
Giant Study Helps Clarify Role of Genes in Same-Sex Sex
Emma Yasinski | Aug 29, 2019
The largest study of its kind to date estimates that genetics accounts for at most 8–25 percent of variation in whether or not a person reports engaging in non-heterosexual behaviors.
funnel web spider courtship
Image of the Day: Spider Sex
Nicoletta Lanese | Aug 26, 2019
Funnel-web spiders change the timing of their distinct courtship behavior depending on what microbes they’re carrying.
sperm mouse sex selection ivf in vitro fertilization x y chromosome
Researchers Develop New Method for Sexing Sperm
Katarina Zimmer | Aug 13, 2019
Scientists found they could sort mouse sperm prior to IVF by treating semen with a drug that selectively slows down X-bearing cells.
chinese pond turtle embryo temperature-dependent sex climate change
Turtle Embryos May Have a Say in Deciding Their Sex
Katarina Zimmer | Aug 1, 2019
In a species of freshwater turtle, embryos can move toward warmer or cooler environments within the egg and thus help choose their sexual destiny, but not all experts are convinced.
chimpanzee testes
Why Chimpanzees Have Big Testes, and Mandrills Have Small Ones
Katarina Zimmer | Apr 16, 2019
For primates, males’ fancier ornaments are linked with smaller testes, according to a new comparative study.
Larger Hermit Crab Penises May Prevent Shell Theft
Abby Olena | Jan 16, 2019
Members of species with shells they must hold onto for survival have larger sexual tubes than those with less precious private property.
Men React to Repeated Painful Experiences Differently than Women Do
Diana Kwon | Jan 14, 2019
Men’s pain tolerance decreases when exposed to a setting where they’ve previously had a painful experience.
Trump Administration’s Definitions of Sex Defy Science
Ashley P. Taylor | Oct 23, 2018
The government wants to limit a person’s sex to male or female as determined by genitalia at birth and genetics. It’s not so simple, say scientists.
Genetic Risk Factor for Erectile Dysfunction Identified
Ashley P. Taylor | Oct 9, 2018
Researchers believe the genetic locus affects the regulation of another gene involved in sexual function.
Fruit Fly Geneticist Bruce Baker Dies
Diana Kwon | Jul 30, 2018
The Stanford University professor was known for his work on sex determination and courtship in flies.