Evolution, 4th Edition

SuGGESTiONS FOR FuRTHER READiNG

Tempo and Mode in Evolution, by G. G. Simpson

(Columbia university Press, New York, 1944),

and Evolution above the Species Level, by b.

Rensch (Columbia university Press, New York,

1959), are classic works of the evolutionary syn-

thesis, in which the authors reconcile macro-

evolutionary phenomena with neo-Darwinian

theory. Punctuated Equilibrium, by Stephen Jay

Gould (Harvard university Press, Cambridge,

MA, 2007), is the posthumously published cen-

tral chapter of his magnum opus, The Structure

of Evolutionary Theory (Harvard university

Press, Cambridge, MA, 2002).

The relation of macroevolution to microevolu-

tionary processes is discussed by D. J. Futuy-

ma, “Can modern evolutionary theory explain

macroevolution?” (pp. 29–85 in Macroevolu-

tion: Explanation, Interpretation and Evidence,

E. Serrelli and N. Gontier [eds.], Springer inter-

national Publishing, Heidelberg, 2015).

The evolution of eyes, and why it is not a mystery,

is the subject of a special issue of the journal

Evolution: Education and Outreach (vol. 1,

issue 4, October 2008). Molecular aspects of

this topic are summarized by T. H. Oakley and

D. i. Speiser, “How complexity originates: The

evolution of animal eyes” (Annu. Rev. Ecol.

Evol. System. 46: 237–260, 2015). N. Shubin

recounts the evolutionary history of the hu-

man body in Your Inner Fish: A Journey into

the 3.5-Billion-Year History of the Human Body

(Allen Lane/Pantheon, New York, 2008).

Developmental and genetic aspects of the origin

of novel characteristics are treated by N. Shu-

bin, C. Tabin, and S. Carroll in “Deep homol-

ogy and the origins of evolutionary novelty”

(Nature 457: 818–823, 2009), and by G. P.

Wagner in Homology, Genes, and Evolution-

ary Innovation (Princeton university Press,

Princeton, NJ, 2014).

Modern paleontological and phylogenetic ap-

proaches to some aspects of macroevolution

are reviewed by G. Hunt and D. L. Rabosky in

“Phenotypic evolution in fossil species: pattern

and process” (Annu. Rev. Earth Planet. Sci. 42:

421–441, 2014), and by G. Hunt and G. Slater

in “integrating paleontological and phyloge-

netic approaches to macroevolution” (Annu.

Rev. Ecol. Evol. System. 47: 189–213, 2016).

PRObLEMS AND DiSCuSSiON TOPiCS

1. Snapdragons (Antirrhinum) and their rela-
   tives in the traditionally recognized family
   Scrophulariaceae have bilaterally symmetrical
   flowers, derived from the radially symmetrical
   condition of their ancestors. A mutation in the
   cycloidea gene makes snapdragon flowers radi-
   ally symmetrical. Should we conclude that evolu-
   tion from radial to bilateral symmetry was caused
   by change in this one gene? Would that be a
   saltation? Are there other possible histories of the
   evolution of bilaterally symmetrical flowers that
   are not saltational but are compatible with this
   observation?


2. Suppose you are studying a genus of living
   organisms that have a fairly short generation time
   and can be bred in captivity. A certain character-
   istic does not differ among these species, and
   looks like a case of evolutionary stasis. How might
   one test whether the stasis is best explained by
   genetic constraints, stabilizing selection, or gene
   flow among divergently selected populations?


3. Would you expect “living fossils,” such as horse-
   shoe crabs, to differ from other species in amount
   of genetic variation, genetic correlations among

characters, canalization (see Chapter 15), or any

other feature that might affect evolvability? Why

or why not?

4. Many creationists will allow that microevolution
   (for example, changing gene frequencies in a
   population) has occurred, and will even acknowl-
   edge that species adapt to different environ-
   ments. However, they deny that macroevolution
   (they define it as the evolution of new “kinds”)
   is supported by evidence. Explain how they are
   mistaken. How might you help a creationist friend
   better grasp how modern scientists consider
   micro- versus macroevolution?


5. Rates of evolutionary change measured over
   short time intervals are often very high. However,
   rates of evolutionary change measured over
   long time intervals are generally much lower.
   For example, see the discussion of body mass in
   mammals in this chapter. Should we expect this
   pattern to hold true for most characters? Does
   this pattern imply that the evolution of major new
   characters, such as the wings of bats, should occur
   very rapidly?

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