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")


[Package ecoteach version 0.1.0 Index]