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of the Pleistocene Epoch (about 12,000 years ago), found that after these mammals
died out, the soils there never quite recovered. The paleoecologists concluded that
the magic ingredient missing from these soils was large-mammal excrement. The
big herbivores—which included giant ground sloths, glyptodonts (armadillo-like
animalsthesizeofacompactcar),andelephantrelatives—hadactedasagricultural
agents, spreading the wealth (so to speak) and donating nutrients to soils wherever
their droppings dropped. Also, because they were big animals, they traveled greater
distances, meaning their dung was distributed far and wide. However, once this co-
pioussupplyofenrichedorganicmatterwasgone,soilssuffered,whichaccordingly
meant plant communities grew less exuberantly and became less diverse.
The main implication ofthis research wasthat the presence oflargedefecating
herbivores was very important for maintaining plant communities during the Pleis-
tocene in that part of South America. Furthermore, their long-time presence prob-
ably affected the evolution of angiosperms there, and few places in the world are
more famous for their floral diversity than the Amazon basin. Likewise, whenever
greatpoopersdieout,oneshouldalsomournfordungbeetles,whichdiewiththem;
this meant that insect biodiversity also declined with the demise of the megafauna.
So now take this concept much further back into the geologic past, such as
during the Cretaceous, and ponder the effects of herbivorous dinosaur feces on en-
riching nutrients insoils andplant growth.Although notall dinosaur feces survived
to become coprolites, these traces surely contributed to the fruition of flowering
plants, and thus the evolutionary legacy of flowering plants embodies these fecal
traces.
Scared Green? The Possible Effects of Predatory Theropods on Vegetation
What about large predatory theropods, those poor neglected dinosaurs that almost
no one seems to care about, nor remember? How did these big carnivores relate
to the evolution of land plants, including flowering ones? Putting oneself in their
places, thick vegetation either would have served as great cover for ambush pred-
ation or gotten in their way when chasing down their prey. But that's thinking too
