<span>Positive Homans'
medical Definition of Homans' sign. : pain in the calf of the leg upon dorsiflexion of the foot with the leg extended that is diagnostic of thrombosis in the deep veins of the area.</span>
The answer is d. Food chain
<span>The wings on
the beetles are examples of vestigiality. Vestigiality is a structure with
attributes that have apparently loss its ancestral function but stil present
during evolution. It is a normal evolutionary process in the changing
environment that does not pressure them to evolve.</span>
B - To live in less extreme environments than most Archaebacteria.<span>♥</span>
The palaeozoic started in a period in which invertebrates started proliferating rapidly and in large amounts, which was considered a historical event and the end of that gigantic era.
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