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uncovered, which suggested that the skull might be preserved some-
where under the surface. In all, it appeared that, except for the end of
the tail, which had weathered awav before Alberto had found the
skeleton, all of the bones might be present.
While reflecting on our new discovery, we realized that another
piece of the ancient puzzle of Auca Mahuevo had fallen into place.
Although we had still not found a good skeleton of the adult sauropods
that had laid the eggs, we now had a pretty good idea about who had
probably served as their primary predator. The parts of the skeleton
that had been exposed showed that this menacing meat-eater was
about twenty feet long. Based on the long, powerful hind legs and
short arms, it clearly walked exclusively on its two back legs and
probably weighed between one and two tons. Although Alberto's
spectacular discovery lay many feet above the egg layer, there was lit-
tle doubt that the species to which it belonged inhabited the area
when the Auca Mahuevo sauropods gathered to nest. It would have
been a terrifying adversary. Such an animal could easily have taken
down a young sauropod bv itself, and if the predators pooled their
efforts in packs, even adult sauropods could have been at risk.
Quarrying of the eggs also continued on March
5.
By now more
than eighty eggs had been exposed, and wc hoped that we would soon
have several hundred eggs excavated and mapped. Unfortunately, the
fickle Patagonian weather had other ideas about how we would spend
the next two days. By the end of the afternoon, clouds were building
on the horizon, and we covered both quarries with large tarps just in
case the torrid summer heat was temporarily interrupted by another
torrent from the approaching fall.
During that night, the rains arrived, though not the kind of tor-
rential downpour that we had experienced earlier on our way to the
site. It was just a gentle, steady rain that lasted for two whole days.
Frustratingly, however, the ground was so muddy that we could not get
to either of our quarries. Even if we had made it, it would have been
impossible to work because the wet clay of the egg-bearing mudstone
would have stuck tenaciously to the tools and fossils, risking damage
to the eggs if we had tried to excavate them. To deny the rain an
opportunity to dampen our spirits, we headed to Plaza Huincul to see
some new exhibits at Rodolfo's museum. Since the last time we had
visited, the museum had finished a new, full-scale mount of the
