Evolution What the Fossils Say and Why it Matters

Cambrian “Explosion”—Or “Slow Fuse”? 175 Still other hypotheses (such as the ideas that they are lichens, proposed by Greg Retal ...

176 Evolution? The Fossils Say YES! Some of the little shellies look like simple cap-shaped or coiled mollusks; others look like ...

Cambrian “Explosion”—Or “Slow Fuse”? 177 (fig. 5.6). By the Tommotian Stage (530 million years ago), a slow trickle of other gro ...

178 Evolution? The Fossils Say YES! Thus we have seen that the “Cambrian explosion” is a myth. It is better described as the Cam ...

Cambrian “Explosion”—Or “Slow Fuse”? 179 Only after several more steps do we see the full Cambrian fauna. In short, the fossil r ...

180 Evolution? The Fossils Say YES! Most scientists ignored it, but the few who wasted their time reading it lambasted it (Cook ...

Cambrian “Explosion”—Or “Slow Fuse”? 181 Briggs, D. E. G., and R. A. Fortey. 2005. Wonderful strife: systematics, stem groups, a ...

FIGURE 8.1. A typical assortment of planktonic microfossils from a deep-sea core. Each is about the size of a pinhead or smaller ...

8 SPINELESS WONDERS OF EVOLUTION Invertebrate Transitions There is a story, possibly apocryphal, of the distinguished British bi ...

184 Evolution? The Fossils Say YES! is yes! Microfossils are used routinely for biostratigraphic correlation by thousands of spe ...

Spineless Wonders of Evolution 185 convergent evolution (Cifelli 1969). In other cases, it is not clear that the skeletal shape ...

186 Evolution? The Fossils Say YES! Let us look at some of many examples of evolution in the well-studied forams first. One of t ...

Spineless Wonders of Evolution 187 large. That idea is confirmed by the fact that fusulinids lived in enormous numbers on shal- ...

188 Evolution? The Fossils Say YES! or Permian, ask a fusulinid expert to look at it, and you will get the most precise estimate ...

Spineless Wonders of Evolution 189 oblong bubbles clustered together in a spiral arrangement (fig. 8.5A). Through the many cores ...

(A) (B) (C) (D) ...

FIGURE 8.5. Evolutionary sequences in some of the planktonic foraminifera. (A) In the Pliocene and Pleistocene, the fingerlike p ...

192 Evolution? The Fossils Say YES! korotnevi). Two lineages that had been distinct for millions of years (Pterocanium praetextu ...

Spineless Wonders of Evolution 193 millions of years, you see them gradually lose their spongy outer layers and develop into a s ...

194 Evolution? The Fossils Say YES! FIGURE 8.8. Evolution of the scallop Chesapecten during the Miocene and Pliocene, as preserv ...