Herbivory Essay

Herbivory can be defined broadly as the act of eating plants adopted by herbivorous organisms for example Bos taurus and Ovis aries. Herbivory acts as an important trophic level in an ecosystem, directly providing energy to the herbivores, and indirectly acting as an energy source to carnivorous organisms. There are a wide variety of herbivorous organisms that have adopted six main feeding strategies; grazers, browsers, granivores, frugivores, sapsuckers and nectarivores. The two most common of these are grazers and browsers. Grazers are organisms such as Equus quagga who eat leafy plant material like grasses whereas browsers mainly eat woody plant material. Browsers include animals such as Madoqua. Granivores can be defined as herbivorous organisms that eat seeds. An example of a granivore is the common pigeon (Columbidae) who are specialised to eat seeds by having a crop and a thick muscular gizzard (Garcia-Amado et al., 2018). Frugivores are animals such as Pongo abelii whose diet mainly consists of fruit. Another feeding strategy is adopted by sapsuckers such as D. pileatus who penetrates woody material and syphons the sap out to eat. Finally, nectarivores are herbivores that feed on nectar, these are usually insects such as Trochilidae. 

In order to successfully gain a sufficient amount of energy from plant matter, herbivores have had to adapt their digestive systems. For example, termites have microbes such as bacteria, protozoa and archaea in the fermenters in their hind gut which are able to break down cellulose and lignin from the woody material that termites consume. Similarly, ruminants such as Bos taurus have a stomach comprised of four compartments. After mastication of plant matter has occurred, the bolus travels down the oesophagus to the rumen where water is added to soften it into a pulp. The pulp is then regurgitated to the oral cavity for further mastication before returning to the rumen where digestive microbes can act upon it. From there…