An organism that eats by osmosis, relying on nutrients diffusing into its body from a higher concentration in its environment.
About 550 million years ago, ambitious aquatic fronds began growing taller and tapped into more nutrient-rich water than found at the seafloor surface. Researchers simulated fluid flow over early multicellular osmo-trophs, which may be early precursors to animals, and found that taller fronds absorbed more nutrients.
The fronds grew up to 2 meters tall at a time when oxygen levels were just beginning to rise on Earth, setting the stage for more complex life to follow, the researchers report February 3 in Current Biology.
David Gold of UCLA discusses what scientists are