lion_reproduction {ecoteach} | R Documentation |
Galapagos Sea Lion Reproduction Data
Description
This dataset contains reproductive performance data for female Galapagos sea lions (Zalophus wollebaeki) collected over a 13-year period in the Galapagos archipelago. The data includes information on mother birth dates, body mass, age at first reproduction, and offspring details. This dataset was used to study life history traits and reproductive trade-offs of this tropical apex predator in an unpredictable habitat.
Usage
lion_reproduction
Format
A data frame with 48 rows and 12 variables:
- MotherID
Unique identifier for the mother sea lion
- MotherBD
Mother's birth date
- exact
Whether the birth date is exact ("Yes"), estimated ("No"), or unknown ("Unknown")
- MotherBirthyear
Year the mother was born
- AgeAtCapture
Age of the mother when first captured (in days)
- AverageOneYearBodymass
Average body mass of the mother at one year of age (in kg)
- PupID
Unique identifier for the pup
- FirstPupBorn
Date when the first pup was born
- OffspringSex
Sex of the offspring ("Male" or "Female")
- SeenSince
Year the mother was first observed
- SeenUntil
Year the mother was last observed
- AFR
Age at first reproduction (in years)
Source
Kalberer, Stephanie, Meise, Kristine, Trillmich, Fritz, & Krüger, Oliver (2018). Reproductive performance of a tropical apex predator in an unpredictable habitat. Dryad Digital Repository. doi:10.5061/DRYAD.6S48579
Examples
# Load the dataset
data(lion_reproduction)
# Basic exploration
head(lion_reproduction)
summary(lion_reproduction)
# Calculate mean age at first reproduction
mean(lion_reproduction$AFR)
# Compare age at first reproduction by offspring sex
boxplot(AFR ~ OffspringSex, data = lion_reproduction,
main = "Age at First Reproduction by Offspring Sex",
ylab = "Age (years)")
# Relationship between mother's body mass and age at first reproduction
plot(AverageOneYearBodymass ~ AFR, data = lion_reproduction,
main = "Body Mass vs. Age at First Reproduction",
xlab = "Age at First Reproduction (years)",
ylab = "Average Body Mass at One Year (kg)")