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Before K/T, it is presumable, e.g., that dromaeosaurs were
gregarious taxa, living in packs having several matrilines of adult females
and one, or more, immigrant adult males. Female theropods would be
philopatric, males dispersing from the pack when reaching sexual maturity.
High ranking females within a pack would begin mating earlier, having shorter
intervals between egg laying, their hatchlings surviving to adulthood more so
than females of lower rank within the pack.
Erm... phew... evidence
please. I'm reluctant to call something a just-so story when the author
works on some IMHO important problems and apparently has some successes in
press/work.
Perhaps, the shattered eggs and littered bones of hatchlings
sometimes found are those of lower-ranking
females.
Is there a need for such an
explanation rather than the usual diagenesis and stuff?
Among larger theropods, intrasexual competition among females
would be more "violent" than among males, resulting in "masculine"
females
So they all
were like hyenas? Statistically improbable, no?
Aggressive, larger-sized females was probably the norm, males
smaller and likely rather meek,
Probable, as seen in
predatory birds. The robust morphotypes are usually considered the females in
fossil theropods, and the gracile ones the males.
i.e., natal males would not mate but immigrant males
would.
Why?
The behaviour of all female theropods would be predicated upon
the number /distribution/defensibility of carcasses/live prey available; this
is observable among spotted hyaenas and female chimpanzees among
mammals.
Hunting in chimpanzees has recently been shown to
only serve the male gangs, not protein needs or anything else. Unfortunately
I've forgot the ref (may have been a recent issue of the German version of
Scientific American citing something else).
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