Answer:
D. all of the above
Explanation:
Australopithecus (first ape-man): Australopithecus is considered as the connecting link between apes and man as they shared the characteristics of both. The fossil records shows that they appeared around 5 million years ago. <em>Australopithecus africanus</em> was about 1.5 meters high and had human as well as ape like features. It was with bipedal locomotion, omnivorous in their diet and had erect posture. It had human like teeth with small canines and large chewing teeth. The brain was more like an ape with the brain capacity of about 500 cc similar to that of an ape. He lived in caves, had projected brow ridges with no chin. Its believed that <em>Australopithecus africanus</em> gave rise to <em>Homo habilis</em> about 2 million years ago.
The earliest species of Homo genus is <em>Homo habilis</em>. They were skill full man also called as handy man or the tool maker. He had erect posture with bipedal locomotion. The teeth were like modern man. He was skilled and made tools with stones. Slowly with evolution the prognathous face changed to orthognathous in cro magnon (<em>Homo sapiens fossilis</em>).
Endocrine glands make chemicals called hormones and pass them straight into the bloodstream. Hormones can be thought of as chemical messages. From the blood stream, the hormones communicate with the body by heading towards their target cell to bring about a particular change or effect to that cell.Mar 30, 2014
The top level of the pyramid
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Your answer is D. thermal energy.
