Wonder how salmon know that it is time to spawn, what tells squirrels
and hamsters to get ready to hibernate, or why so many teenagers fall
asleep at their desks in school?
Welcome to the world of biological clocksthe internal molecular
machines that keep track of time in organisms as diverse as fungi, fruit
flies, plants, and mammals. Join us on a brief tour of some of this
season's events and the rhythms behind them.
Fall Events and Rhythms
- School starts in September. For many teenagers this means an early
wake-up call and less sleep during the week.
- Hibernating animals, such as hamsters, squirrels, and marmots, start
preparing for winter hibernation.
- As temperatures drop, leaves change color from green to spectacular
shades of red, orange, and yellow.
- Atlantic salmon head from the ocean back to the streams where they
were born to spawn.
- Many flowers, such as chrysanthemums, asters, and cyclamens, bloom.
- The harvest of grapes begins in September in many vineyards. Late
fall is a good time to visit vineyards for a taste of their nouveau