By studying an extreme drought that go on 4,200 years ago in what ’s now the island paradise of Mauritius , investigator unveil a mass mortality issue that stamp out thousands of giant tortoises and fogey birds . They were cramped together in a “ deadly cocktail ” of their own feces and toxic bacterium , accord tofindingspublished inThe Holoceneearlier this calendar month .
dodo , who famously pass extinct in the 1600s , were only receive on that modest island east of Madagascar in the Indian Ocean . In the past , a shallow lake on Mauritius call Mare aux Songes was an significant source of freshwater that attracted ( and concentrated ) groups of vertebrate , peculiarly those who do n’t migrate . Nowadays , it ’s an incredibly fossil - plentiful area — or lagerstätte , German for “ storage space ” — that ’s fuck as the “ fossil swampland ”
Many regions around the Indian Ocean depend on monsoon downfall , but the seasonal rains declined dramatically during a menstruation of mood change between 4,400 and 4,100 year ago . " What I want to know was , how did this drought have this graveyard?”University of Amsterdam ’s Erik de Boersays . “ How did so many animals die ? ” So , to retrace the ecosystem ’s response , de Boer and fellow worker combined analyses of geochemistry , pollen , diatom ( a group of algae ) , and paint for a multi - proxy coming .
A prolonged megadrought occurred between 4,190 and 4,130 eld ago , they found , which extend to a mass die - off of island natives in Mare aux Songes — including two species of jumbo tortoises and dodos .
The abruptly increasing aridity triggered regional fires and salinization , while lowering water levels and shrink the water aerofoil — all of which resulted in the further tightness of creature who calculate on this coastal web site . “ per annum , the lake would get some clean water in , however this drinking water turned yucky during the ironic season,”de Boer differentiate Science .
Under these hot , ironic , piquant , and crowded conditions , animal fecal matter build up and up , make a suited environment for toxic cyanobacteria . “ The animals lived around the edges , and the excretion probably got mixed up in the wetlands,“de Boer append . " It ’s like a gravid toilet . ”
In the goal , hundreds of thousands of craniate died from inebriety , dehydration , and trampling , or they were otherwise mire in the muck that result . The giant tortoises and dodos finally bounce back with the returning rains , Science reports , and they pull through for another 3,800 years … until the Dutch go far .
