Most living things on Earth have an internal clock that ticks at the schedule of a circadian rhythm. Environmental factors can throw off this rhythm, and for animals that live in zoos, these factors are different compared to animals living in the wild.
One of these factors is moving an animal to a different time zone for conservation purposes. To understand if animals could get jet lag, a recent study tuned into the clocks of wild and captive pandas in zoos worldwide. Researchers found that pandas did indeed experience jet lag, which meant the panda's internal clocks ran in their native time zone in China even if they were on the other side of the world.
“Animals, including humans, have evolved rhythms to synchronize their internal environment with the external environment,” said Kristine Gandia, a psychology Ph.D. student at the University of Stirling and lead author of the study in a press release. “When internal clocks are not synchronized with external cues like light and temperature, animals experience adverse effects."
What Is a Circadian Rhythm?
Circadian rhythms are mental, physical and behavioral changes that follow a 24-hour cycle. These rhythms usually respond to changes in light and affect living things like plants, animals and microbes. Circadian rhythms influence hormone release, digestion, eating habits and temperatures. In humans, circadian rhythms are most noticeable in sleep patterns.
Changes in the body and environmental factors can affect the circadian rhythm and knock it out of sync, such as jet lag, changes or mutations in specific genes and light from electronic devices at night.
Pandas in the Wild vs. Pandas in Captivity
Pandas in the wild live seasonally synched lives, making them the ideal species for researchers to understand how circadian clocks dictate their behavior. Because pandas prefer to eat specific bamboo species and especially love new shoots, they migrate towards the sprouts every spring. This migratory season also notes the beginning of the breeding season.
Captive pandas living in zoos are monitored 24/7 with public webcams, giving immediate insight to any changes in their behaviors. Scientists can then see how daylight and temperature ranges impact the panda's circadian rhythms and behaviors.
Observing Panda Characteristics and Activities
For the study, researchers noted the panda’s everyday activity, sexual behaviors and any unusual behaviors. To fully understand captive pandas, Gandia and her team used webcams to monitor 11 giant pandas at zoos located within the animal’s natural latitudinal range and outside of it, every month for a year. The scientists did a day’s worth of hourly observations to see how the panda’s behavior changed from season to season.
After reviewing the webcam results, the team found that daylight and temperature were key behavioral cues for the pandas. Their activity peaked three times over 24 hours, including one spike at night, just like their wild counterparts. Adult pandas display sexual behaviors only during the day, making finding mates in the wild easier.
How Captivity Impacts Panda Behavior
Overall, pandas outside their normal latitude range were less active, suggesting that this was due to time changes and daylight differences. “When giant pandas are housed at higher latitudes — meaning they experience more extreme seasons than they evolved with — this changes their levels of general activity and abnormal behavior,” said Gandia in a statement.
Captive pandas were more reactive to zoo-specific cues, like anticipating the zookeepers who brought fresh food in the morning. The panda’s abnormal and sexual behaviors also fluctuated at similar times. Researchers suspect this is due to the animal’s frustration to the inability to migrate or mate as they usually would in the wild. Scientists plan to look further into the panda’s sexual hormones to see how their environment affects their release.
“This could help us further understand how to promote successful reproduction for a vulnerable species which is notoriously difficult to breed,” said Gandia in a statement.
Read More: Why the Red Panda Is Endangered