Beetle fossils found in an ancient lake bed in British Columbia are helping scientists to understand global warming in the past and the present.
Fossilized palm bruchine beetles were discovered at the McAbee fossil site near Cache Creek, BC, by scientists from Simon Fraser University.
The McAbee site contains fossilized remains of plants animals that lived near the lake 50 million years ago, during a period called the Eocene epoch. Wind and rivers carried leaves, flowers, seeds and insects into the lake. Then they sank to the bottom and were preserved in the sediment of the lake bed.
Fossil records show how plants, animals and ecosystems evolve over time. When conditions such as climate or landscape change, plants and animals must either adapt to the changes or migrate to a new location in order to survive. The story of what happened can be seen in the fossils left behind.
The palm beetle fossils found at the McAbee site were an important discovery because they helped scientists determine what the climate in central British Columbia was like during the early Eocene epoch.
The beetles feed only on the seeds of palm trees. Palm trees can only grow where winters are mild – above 8°C – and frost free, so they are an important clue to the climate of an ecosystem. But fossils of palm trees can be difficult to find and identify.
Finding the palm beetle fossils told scientists that, 50 million years ago, the climate in central British Columbia was warm enough for palm trees to grow.
During the early part of the Eocene epoch, from about 56 million years ago to about 49 million years ago, the Earth’s climate warmed rapidly and there were high levels of methane and carbon dioxide in the atmosphere.
This is similar to changes we are experiencing today, so learning about the Eocene climate can help scientists understand modern global warming and the effect it could have on the environment.