Workers of a drywood termite do not work

Area of Science:

• Insect behavior
• Evolutionary biology
• Social organization

Background:

• Social insects like ants and bees display altruism, where workers forgo reproduction to aid relatives.
• This behavior is explained by inclusive fitness, favoring kin selection.
• Termite workers, however, are less understood in this context.

Purpose of the Study:

• To investigate the reproductive behavior of workers in the drywood termite Cryptotermes secundus.
• To determine if termite workers exhibit altruistic behavior comparable to other social insects.
• To understand the evolutionary pathways of sociality in termites.

Main Methods:

• Observation of worker behavior in Cryptotermes secundus colonies.
• Brood addition experiments to assess worker response to increased brood numbers.
• Analysis of developmental pathways for 'large immatures' within the colony.

Main Results:

• Workers in Cryptotermes secundus do not engage in brood care or altruistic helping.
• The majority of individuals, termed 'large immatures', develop into either winged or unwinged reproductives.
• Reproductive development probability was independent of brood presence, indicating no kin selection benefit.

Conclusions:

• Contrary to Hymenoptera workers, Cryptotermes secundus 'large immatures' do not function as altruistic helpers.
• The absence of helping behavior may be linked to the termites living within their food source.
• Complex social living in termites might evolve without initial altruistic helping, with altruism potentially evolving later.