Related Experiment Video
Updated: Jun 19, 2026
10:11
Collection and Long-Term Maintenance of Leaf-Cutting Ants (Atta) in Laboratory Conditions
Published on: August 30, 2022
Nonrelatives inherit colony resources in a primitive termite
Philip M Johns1, Kenneth J Howard, Nancy L Breisch
1Biology Program, Bard College, Annandale-on-Hudson, NY 12504, USA.
Summary
The evolution of eusociality in termites is clarified by studying encounters between unrelated colonies. Replacement reproductives developed from workers, demonstrating ecological factors can drive social evolution.
Area of Science:
- Evolutionary Biology
- Behavioral Ecology
- Social Insects
Background:
- Eusociality, characterized by cooperative brood care and reproductive division of labor, is a paradox, particularly the evolution of sterility.
- Termites, a diploid group with complex societies and diverse castes, offer a unique model for studying eusociality, distinct from haplodiploid Hymenoptera.
Purpose of the Study:
- To investigate the role of ecological factors in the evolution of eusociality using primitive dampwood termites (Zootermopsis nevadensis).
- To understand the origin and behavior of replacement reproductives after colony disruption.
Main Methods:
- Staged encounters between unrelated Zootermopsis nevadensis colonies to simulate natural interactions.
- Observed colony merging, reproductive replacement, and interbreeding after simulated king/queen death.
Main Results:
- Members of merged, unrelated colonies cooperated as a single social unit.
- Replacement reproductives developed from workers of the original colonies.
- These replacement reproductives inherited merged colony resources and sometimes interbred.
Conclusions:
- Ecological factors, such as colony encounters and resource merging, can promote eusociality by enhancing direct fitness of offspring.
- Kin selection, driven by relatedness, may be less critical in the initial evolution of eusociality than previously thought.
- Findings in Zootermopsis nevadensis provide insights into the ancestral conditions that may have facilitated the evolution of complex social systems in termites.
Related Concept Videos
00:57Inclusive Fitness
Most altruistic behavior—in which one animal helps another at a cost to themselves—occurs between relatives. Scientists think these altruistic behaviors evolved because they increase the inclusive fitness of the animal providing help.
00:58Symbiosis
Symbiotic relationships are long-term, close interactions between individuals of different species that affect the distribution and abundance of those species. When a relationship is beneficial to both species, this is called mutualism. When the relationship is beneficial to one species but neither beneficial nor harmful to the other species, this is called commensalism. When one organism is harmed to benefit another, the relationship is known as parasitism. These types of relationships often...
01:03Altruism
Altruistic behaviors are “unselfish” behaviors—those that help another individual at the expense of the individual carrying out the behavior. Despite the negative consequences for the altruistic animal, these behaviors are thought to have evolved for several reasons.
01:26Microbial Interactions: Cooperation
Microbial cooperation involves beneficial interactions in which different species work together for individual or mutual advantage. These interactions can profoundly influence ecological dynamics and evolutionary processes, and they are essential to many pathogenic and symbiotic relationships.Nematode–Bacteria CooperationA striking example is the relationship between the Gram-negative bacterium Xenorhabdus nematophila and the parasitic nematode Steinernema carpocapsae. Juvenile nematodes...
02:02Ecological Niches
All organisms have a position within an ecosystem. The complete set of living and nonliving factors—including food resources, climate, and terrain—that define the position of a given organism are collectively referred to as the organism’s ecological niche.Multiple species cannot occupy the exact same niche within their habitat. If the niches of two or more species overlap to a large extent, the competitive exclusion principle dictates that one species will outcompete the other, forcing it to...
02:40Epiphytes, Parasites, and Carnivores
Plants often form mutualistic relationships with soil-dwelling fungi or bacteria to enhance their roots’ nutrient uptake ability. Root-colonizing fungi (e.g., mycorrhizae) increase a plant’s root surface area, which promotes nutrient absorption. While root-colonizing, nitrogen-fixing bacteria (e.g., rhizobia) convert atmospheric nitrogen (N2) into ammonia (NH3), making nitrogen available to plants for various biological functions. For example, nitrogen is essential for the biosynthesis of the...