Lodgepole Pine Cone Masses

Masses of cones of lodgepole pines (conemass) from 16 different habitat types (habitat) in western North America.

Usage

LodgepolePines

Format

A data frame with 16 observations on the following 4 variables.

habitat

a factor with levels: island absent, island present, and mainland present

conemass

mass of cone

location

island or mainland

squirrels

absent or present

Source

Edelaar, P. and C.W. Benkman. 2006. Replicated population divergence caused by localised coevolution? A test of three hypotheses in the Red Crossbill-lodgepole pine system. Journal of Evolutionary Biology 19: 1651-1659.

References

http://en.wikipedia.org/wiki/Lodgepole_pine

http://en.wikipedia.org/wiki/Red_crossbill

Examples

LodgepolePines
#>             habitat conemass location squirrels
#> 1     island absent      9.6   island    absent
#> 2     island absent      9.4   island    absent
#> 3     island absent      8.9   island    absent
#> 4     island absent      8.8   island    absent
#> 5     island absent      8.5   island    absent
#> 6     island absent      8.2   island    absent
#> 7    island present      6.8   island   present
#> 8    island present      6.6   island   present
#> 9    island present      6.0   island   present
#> 10   island present      5.7   island   present
#> 11   island present      5.3   island   present
#> 12 mainland present      6.7 mainland   present
#> 13 mainland present      6.4 mainland   present
#> 14 mainland present      6.2 mainland   present
#> 15 mainland present      5.7 mainland   present
#> 16 mainland present      5.6 mainland   present
str(LodgepolePines)
#> 'data.frame':	16 obs. of  4 variables:
#>  $ habitat  : Factor w/ 3 levels "island absent",..: 1 1 1 1 1 1 2 2 2 2 ...
#>  $ conemass : num  9.6 9.4 8.9 8.8 8.5 8.2 6.8 6.6 6 5.7 ...
#>  $ location : Factor w/ 2 levels "island","mainland": 1 1 1 1 1 1 1 1 1 1 ...
#>  $ squirrels: Factor w/ 2 levels "absent","present": 1 1 1 1 1 1 2 2 2 2 ...
xyplot(conemass ~ habitat, LodgepolePines)