Unique oestrogen receptor ligand-binding domain sequence of native parrots: a possible link between phytoestrogens and breeding success.

The New Zealand (NZ) native parrots kākāpō, kākā and kea are classified as critically endangered, endangered and vulnerable respectively. Successful reproduction of kākāpō and kākā is linked to years of high levels of fruiting in native flora (mast years). To assess a possible hormonal link between native plants and reproductive success in these parrots in mast years, we examined the ligand-binding domains (LBD) of the progesterone receptor (PR), androgen receptor (AR), estrogen receptor 1 (ESR1) and estrogen receptor 2 (ESR2) in NZ native (kākāpō, kākā, kea and kākāriki) and non-native (Australian cockatiel) parrots and compared them with those in the chicken.

Dynamics of the last glacial maximum Antarctic ice-sheet and its response to ocean forcing.

Retreat of the Last Glacial Maximum (LGM) Antarctic ice sheet is thought to have been initiated by changes in ocean heat and eustatic sea level propagated from the Northern Hemisphere (NH) as northern ice sheets melted under rising atmospheric temperatures. The extent to which spatial variability in ice dynamics may have modulated the resultant pattern and timing of decay of the Antarctic ice sheet has so far received little attention, however, despite the growing recognition that dynamic effects account for a sizeable proportion of mass-balance changes observed in modern ice sheets. Here we use a 5-km resolution whole-continent numerical ice-sheet model to assess whether differences in the mechanisms governing ice sheet flow could account for discrepancies between geochronological studies in different parts of the continent.