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My name is John Torday.
This is the 24th lecture in a series on
evolutionary physiology titled
the Cellular-Molecular Approach to Evolution as Niche Construction.
0:11
Niche construction is the process by which an organism
alters its own or other species environments,
often but not always in a manner that increases its chances of survival.
This is an extrapolation of the cellular molecular mechanism of evolution;
the cell is the original niche construction.
As such, it offers an opportunity to broaden
both approaches to evolution by effectively merging
the concept of the cell as the ultimate niche with ecological concepts of the niche.
Recognition of the continuum,
from unicellular life to ecologic adaptation,
is a fundamental importance in understanding
the functional unity of biology as a mechanism for
the maintenance and perpetuation of life through
evolution based on unicellular first principles.
0:57
Darwin had somewhat of a fascination with earthworms,
which were a prime example of niche construction theory because they
generate their own physical soil environment while digging in the dirt.
The paper cited in this slide shows that DNA methylation determines C. elegans longevity
for example, as indicated experimentally by manipulating one of the methylation genes.
1:20
Protocells formed from lipid sources in the primitive oceans;
poly-cyclic hydrocarbons were present on asteroids that formed the oceans.
Algae have a wet weight lipid content as high as 80 percent by weight, for example.
The moon formed about 90 million years after the Earth formed.
The ocean wave action generated by the moon may have promoted the formation of micelles
or semi-permeable lipid spheres as the basis for cellular evolution.
