<Li> Behavioral: This definition is used to specify if a species or individual is actively consuming both plant and animal materials . (e.g. "vegans do not participate in the omnivore based diet .") </Li> <Li> Physiological: This definition is often used in academia to specify species that have the capability to obtain energy and nutrients from both plant and animal matter . (e.g. "humans are omnivores due to their capability to obtain energy and nutrients from both plant and animal materials .") </Li> <P> The taxonomic utility of omnivore's traditional and behavioral definition is limited, since the diet, behavior, and phylogeny of one omnivorous species might be very different from that of another: for instance, an omnivorous pig digging for roots and scavenging for fruit and carrion is taxonomically and ecologically quite distinct from an omnivorous chameleon that eats leaves and insects . The term "omnivory" is also not always comprehensive because it does not deal with mineral foods such as salt licks and the consumption of plant and animal material for medical purposes which would not otherwise be consumed (i.e. zoopharmacognosy) within non-omnivores . </P> <P> Though Carnivora is a taxon for species classification, no such equivalent exists for omnivores, as omnivores are widespread across multiple taxonomic clades . The Carnivora order does not include all carnivorous species, and not all species within the Carnivora taxon are carnivorous . It is common to find physiological carnivores consuming materials from plants or physiological herbivores consuming material from animals, e.g. felines eating grass and deer eating birds . From a behavioral aspect, this would make them omnivores, but from the physiological standpoint, this may be due to zoopharmacognosy . Physiologically, animals must be able to obtain both energy and nutrients from plant and animal materials to be considered omnivorous . Thus, such animals are still able to be classified as carnivores and herbivores when they are just obtaining nutrients from materials originating from sources that do not seemingly complement their classification . For instance, it is well documented that animals such as giraffes, camels, and cattle will gnaw on bones, preferably dry bones, for particular minerals and nutrients . Felines, which are usually regarded as obligate carnivores, occasionally eat grass to regurgitate indigestibles (e.g. hair, bones), aid with hemoglobin production, and as a laxative . </P>

The following is an example of an omnivore