A Breeding System Derived From Asexual Queen Succession in Termite Colonies From Cold Climate Regions

Area of Science:

• Social insect biology
• Evolutionary adaptation
• Reproductive strategies

Background:

• Social insects exhibit geographic variation in physiology and social systems.
• Subterranean termites (Reticulitermes speratus) in temperate/subtropical regions use asexual queen succession (AQS) for reproduction.
• Asexual queen succession (AQS) involves parthenogenetically produced neotenic queens, boosting reproduction without inbreeding.

Purpose of the Study:

• To investigate the reproductive strategies of subarctic Reticulitermes speratus populations.
• To understand how R. speratus adapts its social system to cold climates.
• To compare reproductive development in subarctic versus temperate populations.

Main Methods:

• Genetic analysis of subarctic R. speratus populations.
• Colony founding and rearing experiments with nymphs and workers.
• Comparison of reproductive development (neotenic vs. alate production) between subarctic and temperate populations.

Main Results:

• Subarctic R. speratus populations undergo inbreeding, with colonies headed by numerous neotenic reproductives.
• Most neotenic queens in subarctic populations are produced sexually, unlike the asexual production in temperate regions.
• Nymphs in subarctic populations show a higher predisposition and capacity to develop into neotenic reproductives compared to temperate populations.

Conclusions:

• Reticulitermes speratus in subarctic regions have adapted to cold by shifting from asexual queen succession (AQS) to inbreeding and neotenic reproduction.
• Sexually produced nymphs in subarctic populations are predisposed to become reproductives, whereas in temperate zones, they primarily develop into alates.
• This highlights the flexible adaptation of reproductive systems in social insects to varying climatic conditions.