Amazing stuff!
"When excavators dug into the Santa Lucía military base north of Mexico City to build a new international airport, ... they cracked open one of the biggest paleontological jackpots ever found in the country. Tusks, skulls, and bones emerged by the thousands: camels, horses, saber-toothed cats, and even a lone human. But the true treasure were the mammoths—more than 500 Columbian mammoths, the giant cousins of the woolly species, had been preserved in the mud of an ancient lake.
Normally, we picture mammoths stomping through the Siberian tundra. These, however, were tropical beasts living high on the Mexican plateau. Against the odds, scientists managed to extract DNA from 61 of their teeth—the first genetic data ever recovered from mammoths that lived this far south. The results, published yesterday in Science, show that Mexican mammoths formed their own lineage, genetically distinct from northern herds.
Their genes suggest that their adaptability—eating not just grasses but shrubs and trees—helped them resist climate swings. But by about 11,000 years ago, these giants had vanished ..."
"... By 2022, ... team had amassed more than 50,000 Pleistocene bones from just 3700 hectares. Among them are at least 500 mammoths, 200 camels, 70 horses, 15 giant ground sloths, as well as the remains of dire wolves, saber-toothed cats, bison, armadillos, birds, freshwater snails—and one human skeleton. ..."
From the abstract:
"Paleogenomic studies suggest that Mammuthus columbi derives from an ancient hybridization between Mammuthus primigenius and Mammuthus trogontherii. While its habitat spanned from North to Central America, available genetic data are limited to temperate regions, leaving gaps in knowledge of the species’ demographic history on the continent.
In this study, we generated 61 capture-enriched M. columbi mitogenomes from the Basin of Mexico, in Central Mexico. Our analysis reveals that these mitogenomes belong to a mitochondrial lineage distinct from other North American mammoths. These divergent mitogenomes suggest a deep population structure in their ancestors, and challenge prior assumptions based on geographically restricted samples. Our findings underscore the importance of wider spatial sampling to reconstruct mammoths’ evolutionary history and demonstrate the feasibility of studying megafauna from tropical latitudes."
Columbian mammoth mitogenomes from Mexico uncover the species’ complex evolutionary history (open access)
Fig. 1. Sampling sites of the specimens analyzed in this study.
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