Geoscience Reference
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as nests of the Australian brush turkey (
Alectura lathami
), can be 2 m (6.6 ft) tall
and 20 m (66 ft) wide. Based on the comparatively modest proportions of
Troodon
nests, the bowl-like structure itself could not have taken more than a few weeks to
dig. These nests have no evidence of having been topped by vegetation, but if they
were, their construction would have taken a bit longer.
Troodon
egg-layingitselfprobablytookacoupleofweeks,assumingthateach
pair of eggs took at least a day to emerge from the mother's two oviducts. These
anatomical traits of
Troodon
mothers are interpreted on the basis of how eggs are
paired. Mentioned earlier as “statistically significant,” you actually don't need stat-
istics to see the pairing, though, as it is obvious in every nearly complete
Troodon
egg clutch studied thus far. As noted before, the eggs also must have been aligned
vertically and stuck in the ground by one or both of the
Troodon
parents. The most
parsimoniouswaytoaccomplishthissortofinteriordecoratingwouldhavebeento:
• Lay two eggs;
• Digtwoshallowholesnexttoeachother,eachslightlymorethanthewidth
of and half the length of an egg;
• Place the eggs in their respective holes, pointy ends down;
• Compact the soil around the eggs;
• Repeat with each new pair of eggs until done;
• Sit above eggs until hatched.
Another intriguing trait of the eggs, when oriented like this, is that they had
a greater concentration of pores toward their exposed tops. More pores were there
so the rest of the embryo living underneath the eggshell could breathe easier in that
position. This, along with all of the other trace and body fossil evidence, implies
thattheeggswerenotburiedunderathickpileofvegetationorsoil,butmorelikely
were protected by a
Troodon
parent sitting above the egg clutch. This is a reason-
able assumption, as the relatively small size of these dinosaurs meant they would
not have crushed the eggs. Additional evidence from body fossils of related thero-
