from The American Heritage® Dictionary of the English Language, 4th Edition
- adj. Having or consisting of many cells: multicellular organisms.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- adj. That has many cells, often differentiated in function.
- n. Such an organism
from the GNU version of the Collaborative International Dictionary of English
- adj. Consisting of, or having, many cells or more than one cell.
from The Century Dictionary and Cyclopedia
- Having several cells; consisting of several cells; many-celled: as, a multicellular organism.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- adj. consisting of many cells
Sorry, no etymologies found.
As any of these authors will agree, the HGT's role is insignificant in multicellular organisms.
Guts: Many unicellular eukaryotes were multifunctional cells, doing many different things, however these became specialized in multicellular organisms.
Many unicellular eukaryotes were multifunctional cells, doing many different things, but specialized in multicellular organisms.
The more precursors we find, and the more specific they seem to be — so that their functions in multicellular organisms would not be easily replaced by other components — the more difficult it is to accept a non-teleological origin.
IOW, if a gene vital in multicellular life forms is present and highly conserved in single-cell life forms (in which it isn't expressed or perform any other vital function), we could conclude that the gene was front-loaded into the genome by a designer of the original genome with the expectation that multicellular life forms would evolve when that gene does get expressed.
For example, this is true for developmental biology and for analysis of the functions of signalling pathways in multicellular organisms.
Since such a creature as the rabbit is formed through the co-operation of a vast multitude of cells, it is called multicellular; the amoeba, on the other hand, is unicellular.
I think that a similar thing to #2 has already happened, only with a particular kind of multicellular animal that we on earth call "spiders".
If we discovered a more advanced life-form, such as some kind of multicellular organism, that would eliminate a much larger set of evolutionary transitions from consideration as the Great Filter.
However, almost as soon as multicellularity arose, it "exploded", producing the fantastic diversity of multicellular animals, plants, and fungi that we see today and in the fossil record of the Phanerozoic.