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in that they needed some way to hold on to a female while copulating. After all, the
negative consequences of a 20-to-30-ton sauropod falling off its mate in mid-coitus
would have caused much more damage than just humiliation in front of sauropod
peers.
This is where the claws of a male sauropod's front feet, such as the first on
eachfootthatpointedintowardtheirmidlines,wouldhavecomeinhandy,actingas
grappling hooks to hold on to the forward sides of a female when mating. However
painful this action might have been for the female, it would have prevented both of
them from toppling over, a mishap that would have had far worse consequences for
both dinosaurs. (Nevertheless, this would have made for a magnificent trace fossil,
perhaps combined with the body fossils of both sauropods that died on impact.)
Trace fossil evidence that might test the “get a grip” hypothesis (also known as the
“hang on, it's going to be a bumpy ride” hypothesis) would be broken or otherwise
damaged front-foot unguals, caused by struggles between male and female sauro-
pods trying to get into the right position, or gouge marks in bones near the front of
a sauropod skeleton, such as on its scapula, ribs, or vertebrae just behind the neck.
However,titanosaurs lackthesefront-footclaws,anabsence thatcalls intoquestion
the “get a grip” hypothesis for these sauropods.
These nests and their egg clutches inspire yet another question, which is
how sauropod mothers laid their eggs without occasioning onomatopoeia such as
“crunch” and “splat.” For instance, from a full standing position, a mother titano-
saur's cloaca might have been as high as 4 to 5 m (13-16 ft) above the ground. An
egg that fell from such a height would have become instantly scrambled upon im-
pact—no matter how soft the substrate—and a very messy multi-egg pile-up would
haveresultedfromnonstoplaying.Clearlythesesauropodshadtoreducetheheight
from which their eggs dropped, or at least slow down their descent.
This could have been done in several ways. One would have been for the saur-
opods to squat low enough that eggs had less distance to fall and hence gener-
ated less force. Alternatively, these mothers may have had an anatomical attribute,
