Who said/wrote the following?

The premise that evolutionary change is necessarily gradual also comes into question. Gould and Eldredge created quite a stir when, some thirty years ago, they pointed out that the pattern of evolutionary change displayed in the fossil record is quite unlike the steady, slow transformation of populations that Darwin seems to have in mind. Their term "punctuated equilibrium" identifies two unexpected features of the pattern. First, species appear in the record abruptly (abruptly, that is, on the geologist's timescale, where the record of a hundred thousand years may be compressed into a bedding plane just a few millimeters thick). Second, the organisms that make up a species commonly remain virtually unchanged for millions of years before going extinct. The reality of this pattern has been extensively confirmed for organisms as diverse as ancient horses and the microscopic protists called foraminifers. The authors, therefore, recast evolution as a tale about the differential success of species. "All substantial evolutionary change must be reconceived as higher-level sorting based on differential success of certain kinds of stable species, rather than as progressive transformation within lineages." Gould and Eldredge would draw a line between two kinds of evolutionary change. One is microevolution, the spread of beneficial gene alleles within a species (for example, the mutant hemoglobins of humans that confer resistance to malaria, or the butterfly pigments that ward off predators). Macroevolution, by contrast, designates that large transitions that involve major innovations (feathers, or myelin) and underlie the divergence of higher taxons. The mechanisms of macroevolution are not well understood, but appear to differ in kind from those that tailor genes one step at a time, and include some form of selection among species.

Gould's arguments, which I have sketched here in abbreviated fashion that does less justice to either their subtlety or their style, have stirred up a tempest among adherents of the hard-edged ("fundamentalist") version of Darwin's church.

[I've temporarily disabled the comments for a short time to let everyone play.]

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