New insights into the life of the dodo are presented in a study in Scientific Reports this week.
Delphine Angst and colleagues examined the microstructure of 22 bones from 22 dodos from different fossil localities on Mauritius in order to gain insights into their reproductive behaviour, growth and moulting habits. Several of the bone samples studied came from juvenile birds and the authors suggest that the dodo experienced rapid growth rates until it reached sexual maturity, but thereafter took several years to attain skeletal maturity.
The authors suggest that extensive calcium resorption observed in the bones of the dodos analysed could be evidence of moulting and they propose that since moult can generate significant changes in the appearance of birds in terms of colour and feather type, this may explain many discrepancies in the descriptions of the dodo in historical accounts.
Based on their findings, which correlate with observations of modern birds in Mauritius and historical descriptions of dodos, the authors propose that the breeding season for dodos started around August, with ovulation in females. After the chicks hatched, their rapid growth then enabled them to reach a robust size to withstand the harsh conditions of the austral summer and cyclone season in the region (November to March). Following the end of the austral summer, moulting began (around March) with the replacement of the feathers of the wings and the tail first. Thus, at the end of July, the moult would have been completed in time for the next breeding season.