Thursday, May 11, 2006


Herbovores are refered to animal that adapted to feed on grass and plant material,the diet in which most of herbivores feed are diferent depending on the environment they live in.Diferent type of herbivores have selcted thier diet to feed on,this because of the accessibilty they have to that foliage.small animal cannot chose the diet of big trees that found in the forest where there is predators so they have to chose area where they can access.

Most of the herbivores are vulnerable to canivores so they chose diet which is not close to the predatores.they prefer to live in grassland where they can live in social groups than in the forest.So they choose feed in the area where there is less adaptation of canivores predator.Most of the diet that many herbivores have, are composed by grass and leaves.

This choosen diet also pose problem during digestion, this because most of the herbivores feed on cellulose which have many energy scource. In most of herbivores, they digest food through enzyme digestion ,and it is dificult for enzym to break down cellulose because it is composed by organic substances .this cellulose can only be broken down by mechanical means ; extended chewing or fermetation

These problem of digestion in herbivores,tend to influence them to maintain bacteria in their stomach for the process of fermetation which simplify digestion.,but even though they use this process it fail to digest vegetarian meals,which take long to be digested .but some solve the problem by having long digestive system.

Animal with long digestive sytem reduce the problem they encounter,for digestion.They reduce the problem by having ruminat stomach, which help to extend chewing as this ruminat keep food for a time being, when feeding and during leisure they return to the mouth for easy for digestion within ruminats this because food undergo extensive fermentation. In the rumeinats theres is lots of bacteria and protozoa,this are micro-organisms which is responsible for breaking down of cellulose.and this cellulose is the main cause of digestion problem in most herbivores.

Some herbivores solve the problem of digestion by growing big,or by becoming giant. This help them, because they will have long digestion which include ruminats.and this long digestion system allows them to digest toughe plants.In most giant herbivores it take a day for them to digest food,so this influence giantism.

Because of cellulose they eat, metabolisim rate increase and it was sugested that animal with high metabolic process can grow rapidly.It mainly happen in animal that live on land.In terristrial environment competion of food resource are great,so for giant herbivores it become simple for them to access higher foliage and also have strength to reach their food. For example, elephent and giraffe,they reach 18 feet high and they can access high foliage,while elephent also reach 18 feet high with weight around 8 to 10 tonnes ,this enable them to use great bulk of tall trees.

This enable many large herbivores to feed on high foliage,while small herbivores feed on grass or small foliage.being large fo this herbivores helps then to maintain body temperature,and also to be less vulnerable to predators. This because having large body also increase the strength that can prevent small predators to attack them.

In nutshell, diet that herbivores choose to feed on have impact on digestion and this influence the change in body structure that most herbivores have.They change their body structure to solve the digestion problem they encounter.and also to have better access to food rescource as there is competition ,large animal can access to high foliage.But all changes that herbivores have of becoming large is because of the problem they met, failing to digest cellulose pose an impact,that’s why we find large animals on land .

Reference :

Chang.A. Is there any evolutionary advantage to gigantism? Did sauropods continue to grow throughout their lives, like some reptiles and fish do?[internet] 2000-October-16[cited 2006-May-10]

2. Findlay A.L.R.: The Gastrointestinal System: an introduction Carnivores, Omnivores and Herbivores[Internet]1998-February[cited 2006-May11]:

3. Kaplan.M.1995. A very brief overview of digestion in green iguanas and other herbivorous lizard species.[internet].2003-August-11[cited 2006-May-11].Available from: