Sugar assimilation underlying dietary evolution of Neotropical bats

Area of Science:

• Zoology
• Evolutionary Biology
• Physiology

Background:

• Neotropical bats exhibit high taxonomic and trophic diversity, making them ideal models for studying diet-driven evolutionary adaptations.
• Dietary specializations in animals often result in significant adaptations in morphology, anatomy, and physiology.

Purpose of the Study:

• To investigate the metabolic responses to different dietary sugars in wild-caught bats.
• To identify the molecular and physiological adaptations associated with diverse bat diets.
• To understand the interplay between diet, genetics, and digestive physiology in mammals.

Main Methods:

• Metabolic assessment of bats fed different sugars.
• Genomic analysis of 22 bat species to identify gene selection.
• Examination of small intestine anatomy and cellular features.
• Hybridization chain reaction (HCR) RNA fluorescence in situ hybridization to analyze gene expression.

Main Results:

• Insectivorous bats showed a distinct metabolic response to trehalose.
• Bats consuming nectar and fruit exhibited significantly higher blood glucose levels after ingesting glucose and sucrose.
• Genomic analysis revealed positive selection for trehalase in insectivores and sucrase-isomaltase in omnivorous/nectarivorous bats.
• Small intestine morphology and cellular traits varied with dietary sugar composition.
• Nectar bats displayed high expression of the glucose transporter gene Slc2a2, while fruit bats showed increased levels of Slc5a1 and Slc2a5.

Conclusions:

• Bat diets strongly influence their metabolic and digestive adaptations.
• Molecular, morphological, and physiological traits are intricately linked in mammalian diet evolution.
• This study provides new insights into the mechanisms of dietary diversification and sugar assimilation in bats.