Populations of Individuals: Understanding Biological Variation from Molecules to Ecosystems

Variation is an inherent component of biology, essential to selection among alternatives during evolution.It is most often associated with genetic variation, or differences among the genes encoded in the DNA inherited from ancestors.Individual organisms receive their genomes from a clonal parent or from the union of gametes.All subsequent cells, tissues, and organs developed from a clone or sexual union carry the same genome, but they exhibit the ability to develop into the diversity of cell types present in the organism.Such variation is influenced by both developmental and environmental factors, often referred to as being due to 'instability' or 'noise.'This book argues that the degree to which individual organisms adapt to this 'noise' is dependent on their sensitivities to these developmental or environmental factors.Focusing on their sensitivity thresholds enables the individuals to be grouped into populations that automatically respond to signal inputs.These sensitivity threshold