Evolution Update

Evolution Update

Surprising Evidence for the Ancient Origin of Modern Peaches

Brandon Kieft January 9, 2016

The recent discovery of 2.5-million-year-old fossilized peach pits in China, in a form nearly identical to the fruits we know and love today, shows that modern peaches preceded modern humans.

Most modern, cultivated fruit and vegetable varieties are a direct product of domestication and selective breeding at the hands of modern humans. Though this close association with humans is well-documented for many edible crops, newly discovered fossilized peach endocarps (pits) from Southwestern China show that nature itself likely produced the modern peach.

Earlier this year, researchers discovered eight fossilized peach pits in ancient rock strata in the Yunnan Province of China. Amazingly, the morphological characteristics of these pits were identical to some varieties on the market today.

These features (which can be seen in the paper published in Scientific Reports, linked below) include familiar characteristics such as an approximate 3x2x1cm oval shape, a single seed, and the presence of deep furrows and wrinkles covering the pit.

Based on the rock in which they were found, the identification of co-fossilized plants, the complete remineralization of the seed and pit tissue, and the inability to carbon date the fossils (radioactive carbon only reliably dates to 50,000 years or more recent), the scientists concluded that the pit specimens were at least 2.5 million years old.

Though it was previously known that the peach is likely native to China, this study shows that it likely evolved in the region even before humans arrived.

The authors speculate that fruitivorous species, perhaps primates and even early human species, helped spread peaches and, as a result, natural selection acted to produce the large, fleshy fruits that we know and love.

Previous to this discovery and analysis, the oldest evidence for the peach came from 8,000-year-old Chinese archaeological records.

The researchers believe that by understanding the origin and evolution of our natural resources, we can make better and more efficient use of them.

Recent Articles

"Why Do Those Flowers Look like Bugs? Or, on the Evolution of Orchids."
A large group of flowering plants, commonly known as Orchids, often have flowers whose shape coincides with that of their insect pollinators. Recent research has shown how this uncanny flower morphology is guided by evolutionary selection.

"How Plants Maintain a Low-Sodium Diet Without Advice from Their Doctors"
Salt tolerance is a critical stress response in many plants and is controlled by a wide variety of interacting genes. Researchers studying sodium transporters in trees from high-salinity environments have characterized the evolution of these genes and determined that they are under strong positive selection in salty soils.

"Evolutionary History of a Widespread, Recently Diverged Antioxidant Enzyme in a Pig Pathogen"
Peroxiredoxins are proteins conserved across all domains of life that protect cells against the threat of reactive oxygen species. Researchers have recently characterized the evolutionary history of an essential peroxiredoxin gene from a common livestock pathogen.

"A New Class of Antibiotics Less Susceptible to Evolutionary-Driven Resistance Development"
Pathogenic bacteria are evolving resistance to our antibiotics at an alarming rate, however, scientists have recently discovered a molecule that may help combat these microscopic killers.