dry.frog {AICcmodavg}

Frog Dehydration Experiment on Three Substrate Types

Description

This is a data set modified from Mazerolle and Desrochers (2005) on the mass lost by frogs after spending two hours on one of three substrates that are encountered in some landscape types.

Usage

data(dry.frog)

Format

A data frame with 121 observations on the following 16 variables.

Individual

a numeric identifier unique to each individual.

Species

a factor with levels Racla.

Shade

a numeric vector, either 1 (shade) or 0 (no shade).

SVL

the snout-vent length of the individual.

Substrate

the substrate type, a factor with levels PEAT, SOIL, and SPHAGNUM.

Initial_mass

the initial mass of individuals.

Mass_lost

the mass lost in g.

Airtemp

the air temperature in degrees C.

Wind_cat

the wind intensity, either 0 (no wind), 1 (low wind), 2 (moderate wind), or 3 (strong wind).

Cloud

cloud cover expressed as a percentage.

cent_Initial_mass

centered inital mass.

Initial_mass2

initial mass squared.

cent_Air

centered air temperature.

Perc.cloud

proportion of cloud cover

Wind

wind intensity, either 1 (no or low wind) or 1 (moderate to strong wind).

log_Mass_lost

log of mass lost.

Details

Note that the original analysis in Mazerolle and Desrochers (2005) consisted of generalized estimating equations for three mass measurements: mass at time 0, 1 hour, and 2 hours following exposure on the substrate.

Source

Mazerolle, M. J., Desrochers, A. (2005) Landscape resistance to frog movements. Canadian Journal of Zoology 83, 455–464.

Examples

data(dry.frog)
## maybe str(dry.frog) ; plot(dry.frog) ...