For the next meeting I've chosen a paper about one of the big ideas in evolutionary biology, that of the major evolutionary transitions during the history of life. This paper examines under what conditions a major evolutionary transition can occur.
Abstract: The evolution of life on earth has been driven by a small number of
major evolutionary transitions. These transitions have
been characterized by individuals that
could previously replicate independently, cooperating to form a new,
more complex life
form. For example, archaea and eubacteria
formed eukaryotic cells, and cells formed multicellular organisms.
However, not
all cooperative groups are en route to
major transitions. How can we explain why major evolutionary transitions
have or haven’t
taken place on different branches of the
tree of life? We break down major transitions into two steps: the
formation of a
cooperative group and the transformation
of that group into an integrated entity. We show how these steps require
cooperation,
division of labor, communication, mutual
dependence, and negligible within-group conflict. We find that certain
ecological
conditions and the ways in which groups
form have played recurrent roles in driving multiple transitions. In
contrast, we
find that other factors have played
relatively minor roles at many key points, such as within-group kin
discrimination and
mechanisms to actively repress
competition. More generally, by identifying the small number of factors
that have driven major
transitions, we provide a simpler and more
unified description of how life on earth has evolved.
Time and place: 10:00-11:00 January 26th, in Argumentet
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