If ever find insect damage on your Cycads, look closely. There might be an army of caterpillars feasting on it! However, if left undisturbed, these caterpillars will become beautiful Gossamer-winged butterflies ❤
Name: Neuropteris ovata
Location: Texas, USA, Markley Formation
Age: 307-315 million years ago, Carboniferous-Permian Periods
About 307-315 million years ago, the swamp forests where Neuropteris lived were disappearing. To help figure out why, scientists put fossilized leaves of Neuropteris, like the one in the photograph, under a microscope.
Scientists reasoned that the amount of carbon dioxide in the atmosphere might be related to the disappearing forests. Atmospheric carbon dioxide affects climate, and swamp forests can only occur under certain climate conditions.
Scientists used leaf pores, called stomata, to track changing amounts of carbon dioxide. Stomata let in carbon dioxide, which plants need to live. The more stomata per leaf, the less carbon dioxide in the atmosphere. If climate changed 306-311 million years ago, leaves of Neuropteris from different parts of that interval should have different stomata densities.
Stomata are small, about 30 times smaller than the width of a human hair. In order to see them, scientists had to prepare fossilized leaves for the microscope. They washed the fossils in acid and other strong chemicals to separate fossils from rock, then put the fossils on a glass slide. Then, they counted.
Scientists studied multiple fossilized leaves of Neuropteris ovata from different time points between 306 and 311 million years. In that time, stomata density dropped, matching an increase in carbon dioxide. Results from the leaves supported the link between the survival of swamp forests and carbon dioxide.
Specimen Number: UT 1185TX42
References:
Cleal, Christopher J., Robert M. James, and Erwin L. Zodrow. "Variation in stomatal density in the Late Carboniferous gymnosperm frond Neuropteris ovata." PALAIOS 14(1999):180-185.
