eyerusalem. what are ungulates? mammals with hoofs mostly eat plants spend ¾ of their time by...

Post on 17-Jan-2016

214 Views

Category:

Documents

2 Downloads

Preview:

Click to see full reader

TRANSCRIPT

Eyerusalem

What are ungulates?

• Mammals with hoofs• mostly eat plants•Spend ¾ of their time by eating and• 80 hours digesting each meal

What is hoof?A hoof is a modified toenail composed of two structures the unguis (a scale- like plate) sub unguis ( softer layer)Hooves are the principal point of contact

between the legs and the ground as a result ungulates are said to have unguligrade limbs

What is hoof?

Rhinoceros Zebra Warthog Wildebeest

evolution of ungulatesFrom one ancestorEvolved to eat tough plants andFlee from fierce predatorsThe first species was up running 60 million

years a go.Since then, a huge diversity of ungulates

have come and gone. Today there are 207 different species

evolution of ungulates

The two major orders of ungulatesArtiodactyls (even-toed ungulates)

Perissodactyla (odd-toed ungulates)

Artiodactyls: the most successful group of large herbivores on earth to day Contains the majority of domesticated mammal. approximately 240 ungulate members of this order show incredible

diversity in size, form dietary preference, and climatic tolerance. The primary distinguishing feature of all the ungulates within this

order is the paraxonic limb structure in which the symmetry of the foot passes between the two middle digits(3&4)

Paraxoinc: pertaining to a state or condition where in the axis of the foot lies between the third and forth digits.

The two major orders of ungulatesPerissodactyla : contains only seventeen living species horses the rhinoceroses and the tapirs

What is the role of hooves? The hoof is a vital to ungulate’s existence.Enables them to adapt their environment Absorb shock provide traction resist wear and fracturing protect the sensitive structure within the hoof

wallsupport body weight conduct moisture throughout the hoof wall. Adjusting the rate and density of growth

Ungulates obtain the speed needed to survive, an evolutionary imperative which would not have been possible with out the development of the hoofs

Raising the heel and digits off of the ground increases the number of joints which move the legs forward.

It increases the rat of stride

How hooves are developed/evolved/?Lifestyle : the development of hooves

illustrates a major innovation in the evolution of running lifestyle, pushed on early ungulates by fast running predators.

structure of hoofs

Early ungulates’ and modern ungulates’ hoofs

Early ungulates’ and modern ungulates’ hoofs

Idea in future researchIf the common ancestor of the two groups of hoofed

mammals alive today was also the ancestor of several groups which don't have hooves at all, what make them related, what cause their difference?

top related