Real World Graduation, Question 66: Charles Darwin

RealWorldGraduation_Question_66_CharlesDarwin   <– PDF

Charles Darwin (1809 – 1882) was an English “naturalist”, that is, a scientist who studies nature and the workings of nature. He is highly regarded as an honest, patient worker who sifted through the facts available to him, testing various hypotheses per the scientific method, until he obtained some measure of consistency that allowed him to propose theories.  His most famous theories have been combined under a general concept of “the theory of evolution”.   He presented his work on “evolution” in two books, The Origin of the Species By Means of Natural Selection (1859) and The Descent of Man and Selection In Relation to Sex (1871).  Consider the following passages from Charles Darwin’s original work; the portions in square brackets are explanatory notes that I have added.

“As species have generally diverged in character during their long course of descent and modification, we can understand why it is that the more ancient forms, or early progenitors of each group, so often occupy a position in some degree intermediate between existing groups. Recent forms are generally looked upon as being, on the whole, higher in the scale of organization than ancient forms; and they must be higher in so far as the later and more improved forms have conquered the older and less improved forms in the struggle for life; they have also generally had their organs more specialized for different functions.  This fact is perfectly compatible with numerous beings still retaining simple and but little improved structures, fitted for simple conditions of life; it is likewise compatible with some forms having retrograded in organization, by having at each stage of descent better fitted for new and degraded habits of life.” [1]

“The similar framework of bones in the hand of a man, wing of a bat, fin of a porpoise, and leg of the horse, — the same number of vertebrae forming the neck of the giraffe and of the elephant, — and innumerable other such facts, at once explain themselves on the theory of descent with slow and slight successive modifications. …  On the principle of successive variations not always supervening at an early age, and being inherited at a corresponding not early period of life, we clearly see why the embryos of mammals, birds, reptiles, and fishes should be so closely similar, and so unlike the adult forms.” [2]

“Throughout whole classes various structures are formed on the same pattern, and at a very early age the embryos closely resemble each other. Therefore I cannot doubt that the theory of descent with modifications embraces all the members of the same great class or kingdom.  I believe that animals are descended from at most only four or five progenitors [ancestors], and plants from an equal or lesser number.” [3]

[Note: Apparently “class” and “kingdom” in this context are synonymous, and refer to mammals, reptiles, birds, fish, and insects. I have inferred this from two sources.  The first is a glossary in The Origin of the Species, in which “mammalia” are called the “highest class of animals”. The second is a section in Chapter 21 of The Descent of Man (paragraph 19) in which Darwin states: “In the several great classes of the animal kingdom,–in mammals, birds, reptiles, fishes, insects, and even crustaceans…”] 

“The main conclusion here arrived at, and now held by many naturalists who are well competent to form a sound judgment is that man is descended from some less highly organized form. The grounds upon which this conclusion rests will never be shaken, for the close similarity between man and the lower animals in embryonic development, as well as in innumerable points of structure and constitution, both of high and of the most trifling importance,–the rudiments which he retains, and the abnormal reversions to which he is occasionally liable, — are facts which cannot be disputed.” [4]

From the preceding statements, which is most likely within the kingdom of mammals, considered over the entire course of earth’s history?

a) That birds are descended from dinosaurs

b) That humans are descended from monkeys

c) That monkeys are descended from tigers

d) That elephants are descended from rabbits

e) That cats are descended from dogs

[1]     Charles Darwin, The Origin of the Species By Means of Natural Selection, Chapter 15 “Recapitulation and Conclusion”, paragraph 30.

[2]     Charles Darwin, The Origin of the Species By Means of Natural Selection, Chapter 15 “Recapitulation and Conclusion”, paragraph 35.

[3]     Charles Darwin, The Origin of the Species By Means of Natural Selection, Chapter 15 “Recapitulation and Conclusion”, paragraph 46.

[4]     Charles Darwin, The Descent of Man and Selection In Relation to Sex, Chapter 21 “General Summary and Conclusion”, paragraph 2

(The answer is on p. 3 of the PDF.)

Tags:

Comments are closed.