National Geographic News
From a bed of volcanic ash deposited in northeastern China more than 124 million years ago, botanists have recovered impressively complete fossils of some of Earth's earliest flowering plants.
The discovery of this new family of plants sheds light on the life and times of early members of an enormous category of flora, which includes flowers, trees, and many life-sustaining crops.
"Flowering plants are the dominant vegetation in the world today," says David Dilcher of the University of Florida in Gainesville, who is one of the new fossil's co-discoverers. "They're the basic food crop and fiber source for the world's population."
Dilcher and his five colleagues, including four Chinese researchers, found the fossil in a sand-colored slab of stone that they extracted from a fossil-rich rock formation northeast of Beijing. They dubbed the fossil species Archaefructus liaoningensis and Archaefructus sinensis. Together, the finds make up the family Archaefructaceae.
"When we study [Archaefructaceae], we're looking at the ancestry of what sustains us in the world today," says Dilcher. "It's useful for us to understand the relationships among flowering plants, especially in this day of molecular genetic manipulations."
The finding could also help scientists understand the evolutionary history of the flowering plantswhere they began and how they gave rise to so many modern species.
Flowers in Water
Based on the age of the rock in which they found it, the fossil's discoverers believe the plant lived at least 124.6 million years ago, during the dinosaur-dominated early Cretaceous period.
That age makes Archaefructaceae among the earliest of flowering plants. Pollen grains of even more ancient flowering plants, dated to about 130 million years ago, represent the oldest known evidence of flowering plants.
Similarly aged fossils have been found of waterlilies, another type of flowering plant that persists today and, like Archaefructaceae, lived in the water.
The same fossil bed yielded evidence of similar flowering plants several years ago, but the fossil traces of the organism were much less complete, and Dilcher and his colleagues were forced to guess about certain characteristics.
"These are the earliest, most complete remains of flowering plants yet discovered," Dilcher says. "What's spectacular about these fossils is that all parts of the plant are present, including the roots, leaves, and reproductive organs."
The nearly intact specimen enabled the researchers to determine that it grew in watery environments. It wouldn't have been able to support its own weight on land.
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