Fish move not just by swimming but also by jumping, burrowing, walking, and flying. Many species though move by undulating their body and caudal fin (the tail fin that is used for propulsion). These body-caudal-fin (BCF) swimmers, as they are called, exert force against the surrounding water to support and move their body in an undulating motion. Traditionally, these fishes were classified based on key morphological traits and then grouped into four expected swimming modes based on four model species: eel, trout, mackerel, and tuna. But do all fish swim in certain ways based on this...

Three-banded panther worms are an incredibly impressive marine animal. Known scientifically as the acoel worm named Hofstenia miamia, these tiny animals that grow to only 500 micrometers can perform one of the greatest feats in the animal world, whole-body regeneration.

Remove Hofstenia miamia’s tail and it will grow another. Remove its head and another one, including everything from a mouth to the brain, will grow in its place. Cut the worm in three separate pieces and within eight weeks there’ll be three fully formed worms. Their power of...

Tardigrades, also known as water bears, are a diverse group of charismatic microscopic invertebrates that are best known for their ability to survive extreme conditions. A famous example was a 2007 trip to space where tardigrades were exposed to the space vacuum and harmful ionizing solar radiation, and still managed to survive and reproduce after returning to Earth. Tardigrades are found in all the continents of the world and in different environments including marine, freshwater, and terrestrial.

Tardigrades have survived all five Phanerozoic Great Mass Extinction events,...

Congratulations to Cassandra Extavour selected as one of 33 Howard Hughes Medical Institute (HHMI) Investigators. Extavour is investigating the ancient origins of germ cells, which are the only cells in the body to pass on their genes, making germ cells central to the process of evolution. Extavour studies the evolutionary processes that led to the formation of the first egg cell. “While my research...