Hu­man en­vi­ron­men­tal ef­fects ev­i­dent in an­cient bird dung

Iran Daily - - Cultural Heritage & Environment -

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, lab­o­ra­to­rye­quip­ 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.


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