Sloths are fascinating animals that have evolved to live high in the trees of tropical and subtropical forests.
They have a low-energy lifestyle that allows them to survive on a diet of leaves, which are low in nutrients and high in toxins.
However, they also face many challenges from environmental fluctuations, such as temperature changes, habitat loss, human disturbance and predation.
How do they adapt to these conditions and cope with the competition from other sloth species?
A new study, published in the journal PeerJ, has shed light on the activity patterns and behavioral adaptations of two sloth species that live together (sympatrically) in the same forest: the three-toed sloth (Bradypus variegatus) and the two-toed sloth (Choloepus hoffmanni).
The study was conducted by Dr. Rebecca Cliffe, founder and Executive Director of The Sloth Conservation Foundation, and her colleagues.
They used micro data loggers to monitor the behavior of both Bradypus and Choloepus sloths over extended periods, ranging from days to weeks.
Flexible and variable activity
The study found that both Bradypus and Choloepus sloths exhibit cathemeral activity patterns, meaning that they are active at irregular and variable intervals throughout the 24-hour cycle, as per Phys.org.
This behavior allows them to take advantage of favorable environmental conditions while minimizing the risk of predation by birds of prey, snakes and cats.
The study also found that there is a lot of variability in activity levels both between individuals and within individuals.
This suggests that sloths have developed diverse strategies to adapt to their surroundings, enhancing their chances of survival in the face of environmental fluctuations.
For example, some sloths may be more active during certain seasons or weather conditions, while others may adjust their activity according to food availability or social interactions.
Temperature effects
The study showed that daily temperature did not significantly influence sloth activity.
However, Bradypus sloths exhibited increased nocturnal activity on colder nights and the nights following colder days.
This indicates a potential correlation between temperature variations and their behavior.
The study speculated that this could be a way for Bradypus sloths to regulate their body temperature, since they have a lower metabolic rate and less insulation than Choloepus sloths.
They may also have a lower tolerance for heat stress than Choloepus sloths.
Alternatively, it could be a way for Bradypus sloths to avoid competition with Choloepus sloths, which are more active during the day and may dominate the best feeding sites.
Also Read: Study Shows How Prehistoric Ground Sloths Turned Into Their Modern Tree-Dwelling Counterparts
Implications for conservation and biotechnology
The study highlighted the link between behavior, physiology and ecology in sloths.
It showed that sloths have a unique biology that makes them adaptable to different environments and conditions, as per Mass Initiative.
They also have complex venoms that contain thousands of unique peptides with various biological activities, such as blocking pain receptors, inhibiting blood clotting or killing bacteria.
The study also showed that sloths have a rich culture that makes them meaningful to the Noongar people of southwestern Australia, who call them mungee or moodjar.
For the Noongar people, mungee is a sacred plant that holds important lore and teachings about how to live in harmony with nature and each other.
The study suggested that conservation policies need to take into account the cultural significance of sloths for Noongar people and their knowledge of their ecology.
It also implied that biotechnology could benefit from exploring the potential uses of sloth venoms for human health and agriculture.
By revealing how sympatric sloths adapt to different environmental challenges in Costa Rica, this study provided valuable insights for further understanding and appreciation of the role of sloths in nature and culture.
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