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Evolution__3rd_Edition

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612 PART 5 / Macroevolution<br />

Further reading<br />

Study and review questions<br />

1 A character (such as tooth size) has been measured<br />

in two populations, at two times (t 1 and t 2 ) (in Myr BP).<br />

x 1 and x 2 are the average sizes of the character (in size<br />

units) at the two times. Calculate the evolutionary rate<br />

in darwins. You may need a calculator that works out<br />

natural logarithms.<br />

x 1 t 1 x 2 t 2 Rate<br />

2 11 4 1<br />

2 11 20 1<br />

20 11 40 1<br />

20 6 40 1<br />

Simpson (1953) remains a good introduction to the study of evolutionary rates; Fenster<br />

& Sorhannus (1991) is a more recent review. MacFadden (1992) is an excellent book<br />

about evolution in fossil horses. Gingerich (2001) updates his work discussed in<br />

Sections 21.1.2 and 21.2. Hendry & Kinnison (1999) discuss some more sophisticated<br />

measures of evolutionary rate than the darwin; their compilation of measurements<br />

yields similar results to those of Gingerich’s discussed in the text, but various adjustments<br />

need to be made before the numbers are directly comparable. See also some<br />

papers in Hendry & Kinnison (2001). See Grant (1986, 1991) on the finches.<br />

The literature on punctuated equilibrium is now vast, but fortunately Gould (2002b)<br />

provides almost a one-stop shop for the theory, evidence, controversy, and broader<br />

implications, as well as references. Benton & Pearson (2001) is a short introduction and<br />

Levinton (2001) contains a critique. Dennett (1995, chapter 10) discusses the controversial<br />

relation with saltationism. Erwin & Anstey (1995) contains papers on fossil<br />

speciation. Several chapters in Jackson et al. (2001) also contain chapters on the topic.<br />

Jackson & Cheetham (1994) is a popular paper about the Caribbean bryozoans, and<br />

Jackson & Cheetham (1999) looks more broadly at the evidence from Neogene benthic<br />

fossils.<br />

2 Gingerich (1983) plotted evolutionary rates against<br />

the time interval used to measure the rate for over<br />

500 evolutionary lineages. (a) What did he find?<br />

(b) How would you interpret it?<br />

3 Review the main predictions of the punctuated<br />

equilibrium and phyletic gradualist models of<br />

speciation in fossils.<br />

4 Describe an evolutionary mechanism that could<br />

generate punctuated equilibrium. Does it imply that<br />

punctuated equilibrium contradicts orthodox<br />

Darwinism?<br />

5 How can it be quantitatively shown whether a<br />

taxonomic group is a living fossil?<br />

..

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