Data from: Tradeoffs, geography, and limits to thermal adaptation in a tidepool copepod
Data files
Feb 26, 2013 version files 22.71 KB
-
brood size.txt
-
days survived without food.txt
-
female body size.txt
-
interbrood interval.txt
-
male body size.txt
-
minimum generation time.txt
-
Sampling locations.rtf
Abstract
Antagonistic correlations among traits may slow the rate of adaptation to a changing environment. The tide pool copepod Tigriopus californicus is locally adapted to temperature, but within populations, the response to selection for increased heat tolerance plateaus rapidly, suggesting either limited variation within populations or costs of increased tolerance. To measure possible costs of thermal tolerance, we selected for increased upper lethal limits for 10 generations in 22 lines of T. californicus from six populations. Then, for each line, we measured six fitness-related traits. Selected lines showed an overall increase in male and female body sizes, fecundity, and starvation resistance, suggesting a small benefit from (rather than costs of) increased tolerance. The effect of selection on correlated traits also varied significantly by population for five traits, indicating that the genetic basis for the selection response differed among populations. Our results suggest that adaptation was limited by the presence of variation within isolated populations rather than by costs of increased tolerance.