Why Did Single-Celled Life Evolve to Multi-Celled Life?

[Gold Barz]

What was the main reason simple single-celled life evolved to complex multi-celled life?

I heard that one reason was that because of free oxygen because the plate tectonics is efficient at recycling.

Also could single-celled life evolve to a multi-celled life even in a less complex planet than Earth?

 

[kalladin]

There could be cooperativity in accessing resources... not too sure though ^^

K

 

[Monique]

You can become dominant if you work together and share tasks.

 

[Gold Barz]

So given time, is there a pretty good chance of that happening?

 

[kalladin]

I think it depends on the complexity of the cell. For example: if you had one HUGE cell with all the functions it could ever need, it would be more efficient to compartmentalize those functions within the cell. Sooner or later due to some freak chance of nature, the cell might just cave in on itself and break off as two cells, each with its own specialized function. This would of course confer higher chance of survival as there would be cooperativity between the cells. But on the other hand, if you had one small cell that only carried out functions necessary for its own propagation, it wouldn't make sense to evolve into a multicellular entity.

 

[Gold Barz]

I see...do you think that some or most of single-cells would evolve into multi-cells?

 

[gerben]

http://www.ncbi.nlm.nih.gov/books/bv.fcgi?db=Books&rid=cell.section.61

 

[Gold Barz]

Thanks for the link gerben, although I don't really understand it lol

 

[gerben]

So given enough time...
Do you think that some single-cells would eventually evolve to multi-cells?

Yes, I would think so. Given that there are already single celled organisms that are dividing and moving away from each other in order not to compete over the local resources. I guess it is inevitable than often things go wrong so that they cannot get away from each other for example because of a mutation they may stick to each other after division. When this occurs they may be worse off than their free conspecifics, but in some of the many cases in which this happens it will happen to a pair that will work better together than that any of them would work alone.

Another way would be that two different species both have an advantage of being close together (the use different nutrients so they do compete), perhaps the waste of the one is food for the other or one changes the local environment that aids the nutrient intake of the other. After a while pairs of them that stick together may arise and because they are good at finding nutrients they will produce much offspring so more and more of these will arise.

 

[Gold Barz]

Thanks gerben, very helpful and I agree with you