Dietary restriction and aging: comparative tests of evolutionary hypotheses

Area of Science:

• Evolutionary biology
• Gerontology
• Animal physiology

Background:

• Dietary restriction (DR) is known to increase lifespan across diverse animal taxa.
• The evolutionary origins of the DR response are not fully understood.
• Adaptation to variable food environments may drive the evolution of DR responses.

Purpose of the Study:

• To investigate the evolutionary basis of the dietary restriction (DR) response using a comparative approach.
• To test predictions regarding the relationship between DR response and life history traits in rotifers.
• To explore the link between reproductive allocation during starvation and lifespan extension under DR.

Main Methods:

• Comparative analysis across 10 species of rotifers.
• Assessment of lifespan and other life history parameters under chronic DR.
• Examination of reproductive allocation strategies during short-term starvation periods.

Main Results:

• Most rotifer species exhibited increased mean and maximum lifespan under DR.
• Interspecific comparisons did not reveal predicted correlations between DR response strength and reproductive traits.
• Species that reduced reproduction during starvation showed increased lifespan under DR, unlike those that continued reproduction.

Conclusions:

• The response to chronic DR in rotifers is linked to reproductive plasticity during starvation.
• Evolutionary adaptation to variable food availability may shape the DR response.
• Reproductive allocation strategies are crucial in mediating the lifespan effects of DR.