Digestive Morphology and Ecophysiology of Herbivorous Mammals

Herbivorous mammals exhibit a remarkable array of morphological and physiological adaptations to process fibrous plant material. Foregut fermenters, such as ruminants, possess multi-chambered stomachs where symbiotic microbes initiate cellulose breakdown before passage to the small intestine. Hindgut fermenters, including many rodents and perissodactyls, rely on an enlarged caecum or proximal colon to house fermentative microbiota downstream of the stomach and small intestine. Variations in gut architecture—ranging from extensive ruminal papillation to deep caecal haustrations—reflect dietary fibre content, body size and feeding ecology. Ecophysiological traits such as gut transit time, enzymatic complement and microbial community structure co-adapt to nutrient availability, enabling efficient extraction of volatile fatty acids, amino acids and simple sugars. Understanding these interconnections is vital for global concerns spanning livestock productivity, greenhouse-gas emissions and wildlife conservation in changing environments.

Research from Nature Portfolio

Recent studies have quantified how frugivorous bats reconcile the demands of flight with digestive efficiency. Despite possessing short intestinal tracts and rapid gut transit, these mammals achieve over 90 percent assimilation of glucose and more than 80 percent of true protein by capitalising on free sugars and amino acids in fruit. This arrangement reduces digestive and foraging energetic costs and reinforces mutualistic interactions between bats and fruiting plants. Morphological streamlining of the gut in flighted mammals thus co-evolves with specialised ecophysiological mechanisms to maximise nutrient uptake from low-protein, high-sugar diets.

Digestive Morphology and Ecophysiology of Herbivorous Mammals publication trend

The graph below shows the total number of articles in digestive morphology and ecophysiology of herbivorous mammals across all publications each year (not limited to Nature Index journals).

Technical terms

Foregut fermenter: A mammal with a specialised multi-chambered stomach where microbes ferment plant fibre before small-intestinal digestion.

Hindgut fermenter: A mammal that relies on an enlarged caecum or colon to host microbial fermentation downstream of the stomach.

Caecum: A blind-ended pouch at the junction of small and large intestines, serving as a primary site for microbial breakdown of cellulose.

Transit time: The duration food remains within the digestive tract, influencing fermentative efficiency and nutrient absorption.

Microbiota: The community of microorganisms inhabiting the digestive tract, essential for fermenting complex carbohydrates and synthesising nutrients.

References

1. Morphological adaptation of the eutherian gastrointestinaltract to diet. Vertebrate Zoology (2018).
2. Small nutrient molecules in fruit fuel efficient digestion and mutualism with plants in frugivorous bats. Scientific Reports (2019).
3. How consistent is 'the dynamic gut'? Complex physiological responses to dietary fiber and protein across three rodent species.. Journal of Experimental Biology (2025).
4. Functional Diversity of Morphologically Similar Digestive Organs in Muroidea Species. Biology Bulletin (2021).