Do greater mouse-eared bats experience a trade-off between energy conservation and learning?

Area of Science:

• Animal behavior
• Physiology
• Neuroscience

Background:

• Torpor is an energy-saving state involving decreased body temperature, observed in bats, rodents, and birds.
• Torpor may interfere with sleep and negatively impact memory consolidation, affecting learning.
• Greater mouse-eared bats (Myotis myotis) commonly utilize torpor during warmer months.

Purpose of the Study:

• To investigate the potential trade-off between energy conservation via torpor and learning abilities in greater mouse-eared bats.
• To assess how ambient temperature during torpor affects learning speed and accuracy.
• To determine if daily torpor impacts memory consolidation in bats.

Main Methods:

• Two experiments were conducted comparing learning in bats exposed to low (7°C) versus higher (22°C) ambient temperatures.
• Learning tasks included food search (with reward) and perch search (without reward).
• Skin temperature and behavioral responses were monitored to assess torpor and learning performance.

Main Results:

• Bats exposed to higher temperatures (22°C) spent more time with elevated skin temperature, especially during food-reward tasks.
• A slight, non-significant trend suggested better accuracy and faster search times at higher temperatures.
• No significant impairment in learning accuracy or speed was observed due to torpor.

Conclusions:

• Daily torpor in well-conditioned bats does not appear to significantly affect memory consolidation for simple tasks.
• Circadian rhythm-associated homeostatic processes may protect memory consolidation during torpor.
• Bats may possess mechanisms to prevent rapid entry into torpor if memory consolidation is critical.