Why does cow and horse have a gap between front teeth and back grinding teeth?

Answer 1

Answer 1:

Because the teeth that used to grow there were "weeded out" by millions of years of evolution in mammalian herbivores. Cows naturally have this space; however most horses are still born with canines, and have these canines extracted by a vet or a person qualified to do equine dentistry.

*Note: Cows are true ruminants, which are animals that have a four-chambered stomach. Bison, elk, deer, antelope, wildebeest, giraffes, goats, sheep, muskox, etc. are animals that are also true ruminants. Horses are not true ruminants, as they only have a simple stomach, and the fermentation process occurs in the cecum; thus equines are called Pseudo-ruminants, or Hind-Gut Fermentors.

Answer 2:

That space in most herbivores is called the interdental space.

Cuspid teeth - "canines" - are for tearing flesh. Ancestors of herbivores had cuspids but it has been several million years since the herbivores branched off and only ate plants. Through evolution, organs and body parts that are not needed for survival gradually disappear. These are called "vestigial" organs or parts. That simply means that they are no longer needed by the species.

Male horses are born with cuspids - presumably they have to do with fighting. They have 4 or 5. Cuspids are nearer the front than the back - nearer to the incisors than to the molars. About 1/4 of females are born with one or more cuspids.

The term, "wolf teeth" is a bit of a misnomer - they have nothing to do with cuspids ("canines"), despite the name. They appear to be true vestigial teeth and have no function. Sometimes they are removed if it is determined that they cause pain to the horse with use of a bit. Also, they can interfere with floating (filing down) of molars, so they might be removed for that reason. Usually, a properly seated bit is just fine - wolf teeth or not. But many people do not know how to properly adjust a bridle, causing any upper wolf teeth to be painful. The bit should sit low. Also, there are bitless bridles that more experienced riders use. They are becoming increasingly popular.

See below for links to a couple of diagrams, showing where the cuspids are, and how they don't interfere with the bit.

Answer 2

Cows and horses have a space between their front incisors and their back molars, called a diastema, to allow for easier chewing and processing of tough, fibrous plant material. The front teeth are used for grabbing and tearing grass or hay, while the back teeth grind and crush the food for digestion.