Dataset from Allison and Cicchetti (1976) of 62 mammal species on the
interrelationship between sleep, ecological, and constitutional variables.
The dataset contains missing values on five variables.
Format
mammalsleep is a data frame with 62 rows and 11 columns:
species
Species of animal
bw
Body weight (kg)
brw
Brain weight (g)
sws
Slow wave ("nondreaming") sleep (hrs/day)
ps
Paradoxical ("dreaming") sleep (hrs/day)
ts
Total sleep (hrs/day) (sum of slow wave and paradoxical sleep)
mls
Maximum life span (years)
gt
Gestation time (days)
pi
Predation index (1-5), 1 = least likely to be preyed upon
sei
Sleep exposure index (1-5), 1 = least exposed (e.g. animal sleeps in a
well-protected den), 5 = most exposed
odi
Overall danger index (1-5) based on the above two indices and other information, 1 = least
danger (from other animals), 5 = most danger (from other animals)
Details
Allison and Cicchetti (1976) investigated the interrelationship between
sleep, ecological, and constitutional variables. They assessed these
variables for 39 mammalian species. The authors concluded that slow-wave
sleep is negatively associated with a factor related to body size. This
suggests that large amounts of this sleep phase are disadvantageous in large
species. Also, paradoxical sleep (REM sleep) was associated with a factor
related to predatory danger, suggesting that large amounts of this sleep
phase are disadvantageous in prey species.
Source
Allison, T., Cicchetti, D.V. (1976). Sleep in Mammals: Ecological and
Constitutional Correlates. Science, 194(4266), 732-734.