First multicellularity: fruiting bodies (Evolution)

by David Turell , Tuesday, August 16, 2016, 15:27 (3019 days ago) @ David Turell

Some unicellular organisms under stress will form fruiting bodies, an early form of multicellularity, and if the stress is severe enough some of the cells become spores to insure survival. Here is a review of an early description. Be sure to look at the pictures:-http://www.the-scientist.com/?articles.view/articleNo/46673/title/First-Micrographs-of-Myxobacteria-Forming-Fruiting-Bodies/&utm_campaign=NEWSLETTER_TS_The-Scientist-Daily_2016&utm_source=hs_email&utm_medium=email&utm_content=32973117&_hsenc=p2ANqtz-_BiwWbJAfXX-7yXSdnTA8ACb7HaCSv1fHd73yf8ZYwrvcb85Qb2BFBku2f0d2t25b2BHqNMiQB2EOHxNte0y_R-ypS5A&_hsmi=32973117-"Starting in the late 1970s, Stanford University's Dale Kaiser worked for years to visualize a certain bacterial phenomenon. Microbiologists had known that, when starved, some soil-dwelling myxobacteria aggregate, forming so-called fruiting bodies full of hardy spores. Yet capturing this behavior in action, Kaiser found, was a challenge.-***-“You can take a long time to describe fruiting body formation and how amazing it is, but those pictures really jump out at you, telling the whole story,” says Rutgers University's Ann Stock, who penned a perspective on the 1982 paper this February (J Bacteriol, 198:602, 2016).-"Other groups have since applied the submerged culture method described by Kaiser and Kuner to further study fruiting body formation in M. xanthus and related species. “It looked like we had an in vitro method of forming fruiting bodies,” says Kaiser.-"The team's images are still reprinted today. Stock says, “These images spoke to me from my many years of listening to Myxococcus xanthus talks,” starting when she was a graduate student. “It's a pretty interesting organism with its multicellular, social lifestyle. It stands out among the bacteria.'”-Comment: Some amoeba also can do this. It is obvious that stress in the environment causes developments of this kind. That is the 'why' part. It is the 'how' part that puzzles me. If the stress is severe and they don't get to the spore phase quickly they don't survive. This is a protective process that had to be developed over time. Non-survivors don't develop anything. Did it appear magically all at once?