ARACHNOLOGY
Tarantulas may use learning and memory to search for food and locate their retreats
image:
A blind cave-dwelling tarantula observed in Mexico.
view moreCredit: Rick C. West
Researchers have documented several cases of spatial orientation in tarantulas living both in trees and in underground burrows. Spatial orientation refers to the ability of an animal to understand where it is in three-dimensional space and how to navigate purposefully within its environment. The observations suggest that tarantulas may remember and reuse information to improve their chances of catching prey or to locate their retreats, for example.
A new study by researcher Alireza Zamani from the University of Turku, Finland, and independent researcher Rick C. West reports on spatial orientation in tarantulas in their natural habitats across North and South America. The observations pertain to both tree-dwelling species as well as burrowing species. All the observed tarantula species showed behaviour that may indicate learning.
Some tree-dwelling individuals were observed leaving their retreats every night and travelling to prey-rich locations about one to two meters away, such as areas near artificial lights that attracted flying insects. After hunting, the spiders returned to the same retreats.
The researchers also reported unusual climbing behaviour in species that normally live in burrows. These tarantulas appeared to adapt to foraging in tree canopies rather than on the ground during the dry season.
Together, these observations suggest that tarantulas may remember and reuse information from previous experiences to improve their chances of catching prey. In addition, in lowland floodplain areas, ground-dwelling tarantulas were seen temporarily moving into shrubs or trees during the rainy season, likely to avoid flooding.
The observed behaviours differ from ontogenetic shifts, which are changes in an animal’s habitat, diet, or behaviour that occur at specific stages of development, typically when it grows from a juvenile to an adult. According to this research, a blind cave-dwelling tarantula from Mexico possibly shows such a shift in foraging behaviour: while juveniles appear to stay closer to fixed retreats, adults move more irregularly and seem less dependent on a permanent retreat. This might be because, as they grow, their energetic demands increase and they begin to hunt larger prey.
Behaviour combines internal signals with external cues
Tarantulas were also observed responding to disturbance by returning quickly and directly to their burrows without hesitation or signs of disorientation. What makes this one of the most important observations of the study is the fact that the blind cave-dwelling tarantula behaved similarly to the tarantulas with vision.
The researchers suggest that this behaviour is likely supported by the spiders’ ability to combine internal body signals related to movement, body position, and direction with environmental information, such as light, vibrations, and chemical cues.
“Previous studies have shown that tarantulas can learn to avoid unpleasant stimuli, navigate complex mazes, and remember spatial locations over time. These abilities suggest that their nervous systems support more flexible behaviour than traditionally assumed,” says the lead author of the study, researcher Alireza Zamani from the University of Turku.
However, the researchers note that the cognitive interpretation remains preliminary. Tarantulas are known to rely heavily on sensory information, particularly chemical and silk-based cues, which may also explain how they recognise retreats and choose foraging sites. Further experimental research will be needed to evaluate the relative roles of learning and sensory mechanisms.
“Overall, studies on spider learning are still relatively recent, especially for tarantulas. Observations from the field, combined with controlled experiments, will be important for understanding how sensory cues, memory, and experience interact to help these spiders navigate and search for prey,” notes Zamani.
The research article was published in the journal Ecology and Evolution.
A female Goliath birdeater, a species that normally lives in burrows, foraging in tree canopies.
Credit
Rick C. West
Journal
Ecology and Evolution
Article Title
Insights Into Spatial Orientation and Cognition in Tarantulas (Araneae: Theraphosidae) Under Natural Conditions, With Notes on Possible Ontogenetic Niche Shifts
