Stunning snails to ice mummy tattoos: 10 of the best science pictures of the week - BBC

A small genetic difference can turn a snail into the mirror image of another. Now, researchers studying Japanese land snails have identified a gene that helps determine whether their shells coil clockwise or counterclockwise, offering new clues into how animals develop their left and right sides. The study, led by researchers at the University of Nottingham and Tohoku University in Japan, examined wild Euhadra snails to understand the biological mechanisms behind this phenomenon, known as chirality. Their findings suggest that subtle variations in a gene responsible for producing a protein called myosin can result in healthy snails with opposite body plans.

Two newly identified snail species have expanded the known diversity of European land snails. The species, Cochlostoma komarnica and Cochlostoma dobrido, are described in a new study published in the open-access Biodiversity Data Journal. Neither species has an English common name yet. Both are small, with cone-shaped shells measuring about 6 mm in length, and they live on limestone rocks where they feed on algae and lichens.

The orange markings indicate that these snails were released in 2026. Staff at St. Louis Zoo in St. Louis, Missouri recently opened up a very special delivery in the mail: an overnight shipment of 500 adult Partula snails.

The Greenland shark is one of the world’s largest sharks, but it grows slowly, at only a few centimetres over several years, hinting at a long lifespan. But until 2016 biologists could only guess at the life expectancy of these little-understood creatures.

This microfluidic device squeezes mouse skin cells as they pass through, loosening their tightly packed DNA so CRISPR tools can reach and switch on genes to make cell reprogramming more efficient. Credit: Song Li Lab/UCLA Human cells hold about two meters (6.6 feet) of DNA, folded and compacted to fit inside a nucleus. That packing is essential for life, but it creates a problem for scientists. Some of the genes that control a cell's identity are buried so deep in tightly packed DNA that gene-targeting tools such as CRISPR activation, or CRISPRa, struggle to reach them.