Human environmental effects evident in ancient bird dung
Human beings first arrived in New Zealand at least 700 years ago. A new study of the dung of nowextinct birds shows how the environment changed with the arrival of people.
The dried dung from five species, one of which still clinging to existence, shows DNA, diet, pathogens and some behavioral patterns, according to the paper published in the Proceedings of the National Academy of Sciences, laboratoryequipment.com wrote.
“The wide diversity of DNA we retrieved from the dung has allowed us to reconstruct many aspects of the behavior and interactions of species that we’ve never been able to see before,” said Alan Cooper, of the Australian Center for Ancient DNA at the University of Adelaide, who led the study.
The fossilized dung, or coprolites, were found in caves and rock shelters spanning New Zealand.
The samples came from four different species of the moa, which were large flightless birds overhunted to extinction by the Maori centuries ago, and also the kakapo parrot, a ground-dwelling parrot that is currently critically endangered with just over a hundred individuals left alive.
The coprolites were dated between 120 to 1,500 years ago. (The center of that timeline is the arrival of the first humans).
The main takeaway from the analysis of the waste matter, according to doctoral student Alexander Boast at Landcare Research, was that the moa occupied an important ecosystem niche in the islands’ beech forests, which has remained unfulfilled for centuries.
“The giant birds were eating a wide range of mushrooms and fungi, including species that are critical for the beech forests that are widespread across New Zealand,” said Boast, in a statement.
“The brightly colored mushrooms remain distinctive parts of these forests today, but it appears they were meant to be eaten and then distributed by the moa.”
The mammals introduced to New Zealand in recent centuries by people of European descent do not pass on fertile spores like the moa once did, Boast added.
The ancient extinct birds showed a whole new natural environment that had been changed by the arrival of humans, added Laura Weyrich, of Adelaide’s ACAD, who performed parts of the analyses.
“Moa coprolites contained a surprising diversity of parasites, many completely new to science,” she said.
“Several parasites appear to be specialized to single moa species, so that a range of parasites became extinct with each moa species. As a result, we have probably underestimated the loss of biodiversity associated with the extinction of the megafauna.”
Previous research by Cooper and colleagues had also looked at the coprolites in some selected sites in New Zealand — but not as widely as the current study.
Australia and the nearby islands had their own unique ecosystems, which were altered by the arrival of Polynesians and other people of European descent. Species vanished along the way, including some unique ones, like the Tasmanian tiger.