That large animals require a luxuriant vegetation, has been a general assumption which has passed from one work to another; but I do not hesitate to say that it is completely false, and that it has vitiated the 5 reasoning of geologists on some points of great interest in the ancient history of the world. The prejudice has probably been derived from India, and the Indian islands, where troops of elephants, noble forests, and impenetrable jungles, are associated 10 together in every ones mind. If, however, we refer to any work of travels through the southern parts of Africa, we shall find allusions in almost every page either to the desert character of the country, or to the numbers of large animals inhabiting it. The same 15 thing is rendered evident by the many engravings which have been published of various parts of the interior.
Dr. Andrew Smith, who has lately succeeded in passing the Tropic of Capricorn, informs me that, 20 taking into consideration the whole of the southern part of Africa, there can be no doubt of its being a sterile country. On the southern coasts there are some fine forests, but with these exceptions, the traveller may pass for days together through open plains, 25 covered by a poor and scanty vegetation. Now, if we look to the animals inhabiting these wide plains, we shall find their numbers extraordinarily great, and their bulk immense. We must enumerate the elephant, three species of rhinoceros, the hippopotamus, the 30 giraffe, the bos caffer, two zebras, two gnus, and several antelopes even larger than these latter animals. It may be supposed that although the species are numerous, the individuals of each kind are few.
By the kindness of Dr. Smith, I am enabled to show 35 that the case is very different. He informs me, that in lat. 24, in one days march with the bullock-wagons, he saw, without wandering to any great distance on either side, between one hundred and one hundred and fifty rhinoceroses - the same day he saw several 40 herds of giraffes, amounting together to nearly a hundred. At the distance of a little more than one hours march from their place of encampment on the previous night, his party actually killed at one spot eight hippopotamuses, and saw many more. In this 45 same river there were likewise crocodiles. Of course it was a case quite extraordinary, to see so many great animals crowded together, but it evidently proves that they must exist in great numbers. Dr. Smith describes the country passed through that day, as being thinly 50 covered with grass, and bushes about four feet high, and still more thinly with mimosa-trees.
Besides these large animals, every one the least acquainted with the natural history of the Cape, has read of the herds of antelopes, which can be 55 compared only with the flocks of migratory birds.
The numbers indeed of the lion, panther, and hyena, and the multitude of birds of prey, plainly speak of the abundance of the smaller quadrupeds: one evening seven lions were counted at the same time 60 prowling round Dr. Smiths encampment. As this able naturalist remarked to me, the carnage each day in
Southern Africa must indeed he terrific! I confess it is truly surprising how such a number of animals can find support in a country producing so little food. The 65 larger quadrupeds no doubt roam over wide tracts in search of it; and their food chiefly consists of underwood, which probably contains much nutriment in a small bulk. Dr. Smith also informs me that the vegetation has a rapid growth; no sooner is a part 70 consumed, than its place is supplied by a fresh stock.
There can be no doubt, however, that our ideas respecting the apparent amount of food necessary for the support of large quadrupeds are much exaggerated. 75 The belief that where large quadrupeds exist, the vegetation must necessarily be luxuriant, is the more remarkable, because the converse is far from true. Mr. Burchell observed to me that when entering Brazil, nothing struck him more forcibly than the splendour of 80 the South American vegetation contrasted with that of South Africa, together with the absence of all large quadrupeds. In his Travels, he has suggested that the comparison of the respective weights of an equal number of the largest 85 herbivorous quadrupeds of each country would be extremely curious. If we take on the one side, the elephants hippopotamus, giraffe, bos caffer, elan,five species of rhinoceros; and on the American side, two tapirs, the guanaco, three deer, the vicuna, peccari, 90 capybara , and then place these two groups alongside each other it is not easy to conceive ranks more disproportionate in size. After the above facts, we are compelled to conclude, against 95 anterior probability, that among the mammalia there exists no close relation between the bulk of the species, and the quantity of the vegetation, in the countries which they inhabit.
1. The author is primarily concerned with
A. discussing the relationship between the size of mammals and the nature of vegetation in their habitats
B. contrasting ecological conditions in India and Africa
C. proving the large animals do not require much food
D. describing the size of animals in various parts of the world
E. explaining that the reasoning of some geologists is completely false
2. The word vitiated most nearly means
A. infiltrated
B. occupied
C. impaired
D. invigorated
E. strengthened
3. According to the author, the prejudice has lead to
A. errors in the reasoning of biologists
B. false ideas about animals in Africa
C. incorrect assumptions on the part of geologists
D. doubt in the mind of the author
E. confusion in natural history
4. The author uses information provided by Dr. Smith to
I supply information on quality and quantity of plant life in South Africa
II indicate the presence of large numbers of animals
III give evidence of numbers of carnivorous animals
A. I only
B. II only
C. III only
D. I and II only
E. I, II and III
5. The flocks of migratory birds are mentioned to
A. describe an aspect of the fauna of South Africa
B. illustrate a possible source of food for large carnivores
C. contrast with the habits of the antelope
D. suggest the size of antelope herds
E. indicate the abundance of wildlife
6. The carnage refers to the
A. number of animals killed by hunters
B. number of prey animals killed by predators
C. number of people killed by lions
D. amount of food eaten by all species
E. damage caused by large animals
7. To account for the surprising number of animals in a country producing so little food , Darwin suggests all of the following as partial explanations except
A. food which is a concentrated source of nutrients
B. rapid regrowth of plant material
C. large area for animals to forage in
D. mainly carnivorous animals
E. food requirements have been overestimated
8. The author makes his point by reference to all of the following except
A. travel books
B. published illustrations
C. private communications
D. recorded observations
E. historical documents
9. Darwin quotes Burchells observations in order to
A. counter a popular misconception
B. describe a region of great splendor
C. prove a hypothesis
D. illustrate a well-known phenomenon
E. account for a curious situation
10. Darwin apparently regards Dr. Smith as
A. reliable and imaginative
B. intrepid and competent
C. observant and excitable
D. foolhardy and tiresome
E. incontrovertible and peerless
11. Darwins parenthetical remark indicates that
A. Burchells data are not reliable
B. Burchells ideas are not to be given much weight
C. comparison of the weights of herbivores is largely speculative
D. Darwins views differ from Burchells
E. more figures are needed before any comparison can be attempted
12. Anterior probability refers to
A. what might have been expected
B. ideas of earlier explorers
C. likelihood based on data from India
D. hypotheses of other scientists
E. former information
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