Snowflake reproduction 2:The snowflakes reproduce by spitting out "propagules" once they reach a large size. Once the propagule has grown (through a series of cell divisions) to be large enough, it too spits out a new propagule.The actual paper is very accessibly written and totally understandable by the average non-creationist:
Snowflake settling: The multicellular yeast clusters look like "snowflakes" as they settle to the bottom of their container.
Snowflake genetic stability: Single cells of snowflake-phenotype yeast regenerate new snowflake-phenotype clusters.
Snowflake size evolution: Time-lapse microscopy of derived rapid settling (left) and slow settling (right) genotypes isolated from 5 minute and 25 minute settling regimes, respectively. Cultures were grown for 24 h, diluted 300-fold, and grown in 0.5 uL YPD. Time-lapse microscopy was performed with images taken every minute for 600 minutes.
Experimental evolution of multicellularity (PDF)
Multicellularity was one of the most significant innovations in the history of life, but its initial evolution remains poorly understood. Using experimental evolution, we show that key steps in this transition could have occurred quickly. We subjected the unicellular yeast Saccharomyces cerevisiae to an environment in which we expected multicellularity to be adaptive. We observed the rapid evolution of clustering genotypes that display a novel multicellular life history characterized by reproduction via multicellular propagules, a juvenile phase, and determinate growth. The multicellular clusters are uniclonal, minimizing within-cluster genetic conflicts of interest. Simple among-cell division of labor rapidly evolved. Early multicellular strains were composed of physiologically similar cells, but these subsequently evolved higher rates of programmed cell death (apoptosis), an adaptation that increases propagule production. These results show that key aspects of multicellular complexity, a subject of central importance to biology, can readily evolve from unicellular eukaryotes..
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