Biology 342 Fall 2014
Karl Menzel and Allie Buckner
This website is a guide to what eusocial behavior is, the mechanisms behind it, how animals could have evolved to become eusocial, and why it might be beneficial for them to be eusocial. Very simply put, eusocial behavior is a colony of many generations of the same species living together, they all share responsibilities, and they tend to be closely related. The most well known examples of eusocial colonies are honey bees and ants.
The Characteristics of Eusocial Behavior
Members are sterile with 1 reproductive female: Usually called a queen, the dominant reproductive female spends all of her life giving birth to the generations that will populate her colony. She is usually fertilized by just a few males, which means that all the members of the colony are very closely related.
Multiple generations live together: Eusocial colonies are large. Naked mole rats can live in groups of up to 300 members, and ants can be found in groups with on average 5,000 individuals.
Members divide labor: With so many babies being born so often, the queen needs help raising all of them on top of protecting the colony and collecting food. The sterile members of the colony are vital parts of the survival of the collective. Some members groom and feed the young. Some members venture out of the colony to forage for food. Some members grow specialized parts to better protect their nest, like in the case of most termites.
How to Understand Eusocial Behavior
One of the best ways to understand Eusocial behavior is to look at how it relates to Nikolaas Tinbergen’s Four Questions. Tinbergen’s questions address how the concepts phylogeny (evolution,) mechanism, ontogeny (development,) and survival value relate to the behavior being observed. The answer to the four questions can be related, so it’s usually best to look at all four aspects of a behavior.
Want to learn about how animals evolved to become eusocial? Go to Phylogeny
Want to learn about how eusocial behavior works? Go to Mechanism
Want to learn about how each individual develops and fits into a eusocial community? Go to Ontogeny
Want to learn about why it might be important to be eusocial? Go to Adaptive Value