Image of sperm hooks (<em>Peromyscus maniculatus</em>)
The Mystery of the Mouse Sperm Hook
Nearly all mouse sperm have hooks on their heads. But new research suggests the structures slow them down—so what exactly is their purpose?
ABOVE: Heidi Fisher
The Mystery of the Mouse Sperm Hook
The Mystery of the Mouse Sperm Hook

Nearly all mouse sperm have hooks on their heads. But new research suggests the structures slow them down—so what exactly is their purpose?

Nearly all mouse sperm have hooks on their heads. But new research suggests the structures slow them down—so what exactly is their purpose?

ABOVE: Heidi Fisher

sperm

A headshot of Matthew Gage
Evolutionary Ecologist Matthew Gage Dies at 55
Amanda Heidt | Apr 20, 2022
The University of East Anglia researcher was best known for his contributions to the study of sexual selection, particularly post-copulatory sperm competition.
Pink rat pups piled on top of each other.
Rat Sperm Generated from Stem Cells
Alejandra Manjarrez | Apr 7, 2022
Researchers report they were able to make functional sperm in a dish, a feat previously only possible for mice.
The Epigenetic Origins of Allergy and Asthma
The Scientist Speaks Ep. 15 - The Epigenetic Origins of Allergy and Asthma
The Scientist Creative Services Team | Feb 26, 2021
Epigenetic marks acquired from environmental exposures throughout life influence human health and may even transcend generations.
Collage of images including sperm, bacteria, coral, and an illustration of a researcher
Our Favorite Cell and Molecular Biology Stories of 2021
Jef Akst | Dec 2, 2021
Beyond The Scientist’s coverage of COVID-19’s molecular underpinnings were many other stories highlighting the advances made in scientists’ understanding of the biology of cells.
One hand holds a white envelope with a blue and red striped border, while a second hand places a clear sheet of plastic inside with small squares of paper on it
Freeze-Dried Mouse Sperm Sent by Postcard Produces Baby Mice
Amanda Heidt | Aug 5, 2021
Rather than relying on samples that need to be shipped in glass vials and on ice, researchers have developed a new method that allows mouse sperm to be sent easily at room temperature using standard mail delivery.
Unearthed: World’s Oldest Animal Sperm—And It’s Giant
Max Kozlov | Dec 1, 2020
The sperm, belonging to a tiny marine crustacean, dates back nearly 100 million years, making it the most ancient animal sperm found to date.
Women’s Cervical Mucus Prefers Some Sperm Over Others 
Abby Olena | Aug 18, 2020
In human male-female pairs with a less similar suite of genes for human leukocyte antigens, sperm fare better when exposed to cervical mucus.
Image of the Day: Scrambled Frog Eggs
Emily Makowski | Nov 6, 2019
Cellular innards can reorganize themselves to form structures similar to cells.
Human Testicles Contain Endocannabinoid System Components
Ruth Williams | Sep 19, 2019
Proteins that synthesize, bind, and degrade endocannabinoids are present in the body’s sperm factories, suggesting that the use of cannabis may directly affect them.
Image of the Day: Synchronous Spawning
Emily Makowski | Sep 9, 2019
Groups of corals release all of their eggs and sperm once a year, but the timing of their spawning is under threat from climate change.
sperm motility tracking software flagella swimming movement fertility
Image of the Day: Motile Swimmers
Chia-Yi Hou | Jun 12, 2019
Scientists track the movement of sperm flagella.
Image of the Day: Sperm Donors
Carolyn Wilke | Mar 18, 2019
Asexual female nematodes use their male offsprings’ sperm to fertilize eggs, but cast away their genes.
Image of the Day: Self-Insemination
Carolyn Wilke | Feb 1, 2019
Videos reveal how a female squid fertilizes her eggs—one at a time and without spilling much stored sperm.
Image of the Day: The Long and Short of It
Sukanya Charuchandra | Aug 20, 2018
For flycatchers, the attractiveness of male birds is tied to the length of their sperm.
Researchers Develop Sperm-Robot Hybrids to Deliver Drugs, Assist Fertilization
Diana Kwon | Apr 1, 2018
The artificially motorized cells may one day help fight cancers in the female reproductive tract.
Researchers Cryopreserve Coral Sperm
Catherine Offord | Feb 1, 2018
A project aims to preserve samples of the climate change–vulnerable animals for future restoration.
Coral Sperm Banker
The Scientist Staff | Jan 31, 2018
Mary Hagedorn is racing to save Earth’s coral reefs by developing techniques for freezing the colonial animals’ gametes.
New Techniques Detail Embryos’ First Hours and Days
Jef Akst | Dec 1, 2017
New technologies reveal the dynamic changes in mouse and human embryos during the first week after fertilization.
Infographic: How Embryos Take Control of Their Own Development
Jef Akst | Nov 30, 2017
The switch from maternal factors involves dynamic reprogramming of the zygotic genome.