whale_brains {ecoteach} | R Documentation |
The Evolution of Hearing and Brain Size in Eocene Whales
Description
A dataset containing endocranial volume and body mass measurements for various cetacean (whale) species and other mammals. This dataset was compiled to study the evolution of hearing and brain size in Eocene whales. It includes both extant (living) and fossil species, with a focus on understanding how brain size evolved in relation to body mass and hearing adaptations across different taxonomic groups. The dataset is particularly valuable for teaching concepts in comparative anatomy, allometry, and cetacean evolution.
Usage
whale_brains
Format
A data frame with 269 rows and 9 variables:
- family
Taxonomic family of the species
- binomial_name
Full taxonomic name for each species
- common_name
Common name for each species (NA for most fossil species)
- endocranial_volume
Endocranial volume in cubic centimeters (cc)
- brain_mass
Brain mass in grams
- ocw_mm
Occipital condyle width in millimeters
- body_mass
Body mass in kilograms
- taxonomic_group
Categorization as "Cetacean", "Hippopotamid", or "Other Mammal"
- time_period
Classification as "Extant" (living) or "Fossil" species
Details
Toothed whales (odontocetes) use high-frequency sounds to echolocate, differing significantly from baleen whales (mysticetes), which use low-frequency sound for long-distance communication. This dataset helps explore how hearing functioned in ancestral archaeocetes, and when the specializations of modern species arose.
Source
Peacock, John and Waugh, David and Bajpai, Sunil and Thewissen, JGM (2025). The evolution of hearing and brain size in Eocene whales. Dryad Digital Repository. doi:10.5061/DRYAD.SF7M0CGH1
Examples
# Load the dataset
data(whale_brains)
# Basic exploration
head(whale_brains)
summary(whale_brains)
# Compare brain mass across taxonomic groups
boxplot(whale_brains$brain_mass ~ whale_brains$taxonomic_group,
main = "Brain Mass by Taxonomic Group",
ylab = "Brain Mass (g)", log = "y")
# Look at the relationship between brain mass and body mass
# Using log scales to show allometric relationships
plot(whale_brains$body_mass, whale_brains$brain_mass,
log = "xy", col = as.numeric(whale_brains$taxonomic_group),
pch = 16, main = "Brain Mass vs. Body Mass",
xlab = "Body Mass (kg)", ylab = "Brain Mass (g)")
legend("topleft", legend = levels(whale_brains$taxonomic_group),
col = 1:3, pch = 16)
# Compare fossil and extant cetaceans
cetaceans <- subset(whale_brains, taxonomic_group == "Cetacean")
boxplot(cetaceans$brain_mass ~ cetaceans$time_period,
main = "Brain Mass in Fossil vs. Extant Cetaceans",
ylab = "Brain Mass (g)", log = "y")