DOI: 10.5061/dryad.g89m0
title: Data from: Tradeoffs, geography, and limits to thermal adaptation in a tidepool copepod

description: 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.
description: days survived without
 foodDays survived without
 food for adult female Tigriopus californicus from lines selected for
 increased thermal tolerance and for lines held as unselected controls.
 First line of file is line name. First two letters are two-letter
 population code (see sampling locations file), followed by line number,
 followed by -U for unselected or -S for selected lines.female body
 sizeBody length (in mm) of
 adult female Tigriopus californicus from lines selected for increased
 thermal tolerance and for lines held as unselected controls. Second column
 is population name (see sampling locations file). Third column is
 selection status: S = selected line U = unselected line. N= 6 individuals
 per line, 3-4 selected and unselected lines per
 populationmale body
 size#
 Body length (in mm) of adult male Tigriopus californicus from lines
 selected for increased thermal tolerance and for lines held as unselected
 controls. # first column is population name (see sampling locations file).
 # second column is selection status: S = selected line U = unselected line
 # N= 6 individuals per line, 3-4 selected and unselected lines per
 populationbrood
 size#
 Mean number of larvae from the first 3 broods of females from lines
 selected for increased thermal tolerance and from lines held as unselected
 controls. # second column is population name (see sampling locations
 file). # third column is selection status: S = selected line U =
 unselected line # N= 6 individuals per line, 3-4 selected and unselected
 lines per populationinterbrood
 interval# Mean number of days
 between broods for the first 3 broods of females from lines selected for
 increased thermal tolerance and from lines held as unselected controls. #
 second column is population name (see sampling locations file). # third
 column is selection status: S = selected line U = unselected
 lineminimum generation
 time#
 minimum generation time (in days) for females from lines selected for
 increased thermal tolerance and from lines held as unselected controls. #
 second column is population name (see sampling locations file). # third
 column is selection status: S = selected line U = unselected
 lineSampling
 locationssampling locations and
 abbreviations for Tigriopus californicus