Stream dwellers gather in different combinations depending on location.
Water doesn’t reach all streambeds evenly. And, as it travels, it picks up different chemicals and lifeforms depending on which soil it contacts. In a short stream that flows every summer, organisms form mutually supporting groups that need all that water but few nutrients. At the end of a long stream, you might find communities that thrive together on more and in less water.
Researchers are now testing what rising temperatures will do to streams. Will these diverse communities disappear when more water consistently fills the streambeds?