[dinosaur] Oviraptorid nesting biology with hatching asynchrony (free pdf)

Ben Creisler
[email protected]

Free pdf:

Tzu-Ruei Yang, Thomas Engler, Jens N Lallensack, Adun Samathi, Malgorzata
Makowska & Burkhard Schillinger (2019)
Hatching asynchrony in oviraptorid dinosaurs sheds light on their unique
nesting biology .
Integrative Organismal Biology, obz030
doi: https://urldefense.proofpoint.com/v2/url?u=https-3A__doi.org_10.1093_iob_obz030&d=DwIBaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=tmJLMU5_Bnxpy2RhntoH3NwvcI-1izf6MraTwp1_e8I&s=BCQy0Kz8hvmg-FKD9MjTwkxFeI1Xs_9EYP7pby8rjuI&e= 
https://urldefense.proofpoint.com/v2/url?u=https-3A__academic.oup.com_iob_advance-2Darticle_doi_10.1093_iob_obz030_5626189&d=DwIBaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=tmJLMU5_Bnxpy2RhntoH3NwvcI-1izf6MraTwp1_e8I&s=2lkK_AAsN8zVFXcZ4a7fnTSi35cWTuNEJsgISUL7ygQ&e= 


Dinosaur nesting biology has been an intriguing research topic, though
dinosaur behaviors were relatively less illuminated because of the
constraints of the fossil record. For instance, hatching asynchrony, where
eggs in a single clutch hatch at different times, is unique to modern
neoavian birds but was also suggested to be present in oviraptorid
dinosaurs based on a possible partial clutch of four embryo-containing eggs
from Mongolia. Unfortunately, unequivocal evidence for the origination of
these eggs from a single clutch is lacking. Here we report a new, better
preserved partial oviraptorid clutch with three embryo-containing eggs--a
single egg (egg I) and a pair (egg II/III)--from the Late Cretaceous
Nanxiong Group of Jiangxi Province, China. Geopetal features indicate that
the pair of eggs was laid prior to the single egg. X-ray tomographic images
in combination with osteological features indicate that the embryo of the
single egg is less developed than those of the paired eggs. Eggshell
histology suggests that the embryo-induced erosion in the paired eggs is
markedly more pronounced than in the single egg, providing a new line of
evidence for hatching asynchrony. The inferred hatching asynchrony in
combination with previously surmised thermoregulatory incubation and
communal nesting behaviors very likely suggests that oviraptorid dinosaurs
presented a unique reproductive biology lacking modern analogs, which is
contrary to the predominant view that their reproductive biology was
intermediate between that of modern crocodiles and birds.