The Evolutionary Effects of Digestion on the Brain

• Main Author: Bean, Asher
• Format: Text
• Language: unknown
• Published: UVM ScholarWorks 2019
• Subjects: Canis lupus
• Online Access: https://scholarworks.uvm.edu/src/2019/program/209

There are drastic deviations in digestive systems and brain size amongst species. It is unknown how the brain evolved in conjunction to the development of these differing digestive systems. To determine a potential relationship between brain size and type of digestive system, we looked at brain areas associated with digestive function and the taste perception pathway in monogastric carnivores (Felis Catus, Canis lupus familiaris, and Delphinus), monogastric herbivores Oryctolagus cuniculus, Equus quagga, and Mus musculus), and ruminant herbivores (Ovis aries, Cervidae, and Bos taurus). A brain atlas of the bovine brain was created and compared across nissl stained atlases of other species. The volume of the lateral hypothalamus, solitary nuclei, and ventral posteromedial nucleus (VPN) was measured for each selected species. In order to standardize and compare the brains, a ratio of regional volume to total volume was calculated for each species. Based on the relationship of tissue function, digestion, and eating behaviors in mammals, we hypothesize a larger lateral hypothalamus in ruminant herbivores compared to monogastric herbivores and carnivores. Additionally, monogastric and ruminant herbivores will have a larger solitary nuclei and VPN than monogastric carnivores. This study hopes to determine how diet has evolutionarily affected the development of the brain. Tissues with the greatest difference between digestive systems may be evolutionarily important in digestion and have the potential building blocks for determining how human diet and digestion may influence brain structure and function.