DragonflyIssuesInEvolution13 Wiki

Different beak shape and size evolution of Darwin's finches.


Phenotypic Plasticity


I've been having trouble remembering what Phenotypic Plasticity is (sounds way too much like elasticity from a former career!). 

Phenotypic Plasticity definition[]

My definition (culled from multiple sources):  Phenotypic Plasticity is the way in which an individual changes its morphology (the form and structure of an organism), physiology (the internal working os an individual like metabolism and reproduction), behavior or life history in response to changing environmental conditions. In other words - the ability and capacity of individuals with the same genotype (genetic makeup - not the physical appearance) to exhibit different development patterns, or physical characteristics, or behavior based on variances in environmental conditions.

Valuable resource[]

This paper was extremely useful in helping me to wrap my head around the words "phenotypic plasticity."


Examples of Phenotypic Plasticity[]

Temperature Dependent Sex Determination (TDSD): TDSD refers to the effect that temperature can play on the sex of an organism's offspring. Examples include many species of reptiles, where the temperature in the nest during inclubation affects the sex of hatching offspring.


TDSD in Mountain Dragons


Shine, R. (1999). Why is sex determined by nest temperature in many reptiles? Tree 14 (5): 186-189.

Tyson, K.(2013). TDSD in Mountain Dragons. Retrieved from http://youtu.be/Dz2nUQL3dEM .

Implications of phenotypic plasticity

The ability of an organism to exhibit phenotypic plasticity is especially important and relevant when considering how organisms can adapt to dramatic change like climate change. It seems likely that organisms that have more phenotypic plasticity will fare better than those with less plasticity in a dramatically changing climate. Vedder, Bouwhis, and Sheldon (2013) looked at the phenotypic plasticity of small birds (great tits) over 51 years to determine how they might adapt to climate change. These birds showed great potential for adapting to climate change by showing the plasticity to match their breeding time to when food will be most abundant seasonally. Because they are short-lived, regularly breeding birds, they can adapt more quickly and show promise for climate change. This same study cautions that longer-lived birds, who usually breed less often and take longer to become sexually mature, may have a harder time adapting to climate change.
Looking at phenotypic plasticity in the bigger picture and in terms of climate change, it seems like something that most organisms would benefit from.

Vedder O., Bouwhuis S., & Sheldon B.C. (2013). Quantitative assessment of the importance of phenotypic plasticity in adaptation to climate change in wild
bird populations. PLoS Biology, 11 (7), 1-10.