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Evolutionary clock: nonconstancy of rate in different species
Science (New York, N.Y.)
|August 11, 1972
Summary
Rattlesnake cytochrome c evolved faster than snapping turtle cytochrome c, indicating evolutionary rates depend on species and time. This finding impacts our understanding of molecular evolution in reptiles.
Area of Science:
- Evolutionary biology
- Molecular evolution
- Comparative genomics
Background:
- Cytochrome c is a vital protein in cellular respiration.
- Analyzing cytochrome c sequences aids in understanding evolutionary relationships.
- Reptiles offer insights into vertebrate evolution.
Purpose of the Study:
- To compare the evolutionary divergence of rattlesnake cytochrome c to other species.
- To investigate the species-dependency of evolutionary rates for cytochrome c.
Main Methods:
- Comparative analysis of polypeptide sequences.
- Utilizing established methods for sequence comparison.
- Focusing on cytochrome c protein sequences.
Main Results:
- Rattlesnake cytochrome c shows more rapid evolutionary divergence than snapping turtle cytochrome c.
- The evolutionary rate of cytochrome c differs between rattlesnakes and snapping turtles.
- Comparative analysis revealed significant differences in evolutionary rates.
Conclusions:
- Cytochrome c evolutionary rates are species-dependent.
- Both time and species influence the rate of molecular evolution.
- Findings suggest variable evolutionary dynamics within reptiles.
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