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Improving 2D and 3D Skin In Vitro Models Using Macromolecular Crowding

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Evolutionary layering and the limits to cellular perfection.

Michael Lynch¹

¹Department of Biology, Indiana University, Bloomington, IN 47405, USA. milynch@indiana.edu

Proceedings of the National Academy of Sciences of the United States of America

|November 2, 2012

Summary

This summary is machine-generated.

Random genetic drift limits molecular perfection by natural selection. While new cellular features can improve fitness, these gains are often temporary, increasing complexity without long-term adaptation.

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Area of Science:

Evolutionary Biology
Molecular Biology
Cell Biology

Background:

Observations in biochemistry and cell biology show numerous molecular adaptations.
Experimental manipulation can improve cellular infrastructure, questioning the limits of natural selection.

Purpose of the Study:

To investigate the factors limiting molecular perfection achievable by natural selection.
To explore the role of random genetic drift in hindering adaptive molecular refinements.

Main Methods:

Theoretical analysis of evolutionary processes.
Examination of the impact of genetic drift on molecular adaptations.

Main Results:

Random genetic drift acts as a significant barrier to molecular refinements driven by adaptive processes.
Novel cellular features may offer transient fitness improvements.
Increased molecular and cellular complexity can arise without long-term adaptive benefits.

Conclusions:

Natural selection's ability to achieve molecular perfection is constrained by random genetic drift.
Evolutionary increases in complexity may not always equate to enhanced long-term adaptation.
Apparent advancements can incur increased energetic and mutational costs.