If you’re considering getting your first freshwater tropical fish aquarium then these are the finned friends that should be topping your list.

Revised: This Reviewed Preprint has been revised by the authors in response to the previous round of peer review; the eLife assessment and the public reviews have been updated where necessary by the ...

This valuable study describes an interesting infection phenotype that differs between adult male and female zebrafish. The authors present data indicating that male-biased expression of Cyp17a2 ...

As someone who considers themselves a bird person, I’m aware of the many different examples of courtship displays between male and female birds. Courtship displays can include special movements, songs ...

Not only is this species new to science, but this remarkable individual is the first record of a rare biological phenomenon (bilateral gynandromorphism) in this previously unknown species. One of the ...

In the western forests of Thailand, a burrowing creature that was both male and female was discovered. Maria Krasnova via Unsplash As a scientist, discovering and describing a new species is rare.

Hi, I’m Luke! I’m passionate about buying, selling, breeding, and keeping goldfish — and I’ve built a space to share everything I’ve learned along the way. Whether you’re new to goldfish keeping or a ...

College students are showing up with tote bags, wired ear buds and matcha lattes for a chance to win “performative male” contests that have popped up on campuses around the country. The goal in these ...

Biological sex is usually described in simple binary terms: male or female. This works well for germ cells (sperm versus eggs), but for other body organs it is of little help. A new study by the Max ...

Elise Huchard receives funding from CNRS and the French Agence Nationale pour la Recherche (ANR). Nikos Smit does not work for, consult, own shares in or receive funding from any company or ...

Daniel Liberto is a journalist with over 10 years of experience working with publications such as the Financial Times, The Independent, and Investors Chronicle. TrixiePhoto / Getty Images A 2025 NBER ...