Photo Credit: Matthew D Potenski
Many animals live in complex environments that are constantly changing. In response to such environments many organisms have evolved different levels of phenotypic plasticity that allow for short- and long-term adaptive changes in morphology and behaviour. One such adaption is learning, which is most commonly defined as a change in behaviour as a result of experience. Learning plays a significant role in the behavioural flexibility of fish in a wide range of contexts, including orientation, anti-predator behaviour and foraging. Recent evidence has suggested that some of the learning abilities of teleost fishes are comparable to land vertebrates and that the processes used are strikingly similar. Dr. Gruber pioneered some of the first shark learning studies here we highlight these and describe some more recent findings where sharks learn from each other!
- How do sharks compare to other animals in their ability to learn a classical conditioning regime?
- Are lemon sharks able to learn from each other?
Studies investigating learning behavior in sharks provide important information about shark ecology and have implications for fisheries and ecotourism practices. They also all us to investigate how learning processes evolved across the vertebrate lineage. In the public domain, sharks have a poor reputation they are often referred to as ‘mindless killers’ or ‘swimming noses’ and attacks on humans, albeit rare, gain huge exposure. However, despite this negative press and hysteria surrounding sharks there still remains a real interest and fascination with them, thus studies investigating learning may also help to change public perception.
- Classical conditioning of the nictitating membrane response in juvenile lemon sharks
- Classical conditioning of the nictitating membrane response occurred reliably in lemon sharks.
- Lemon sharks had comparable learning characteristics to mammals, with lemon sharks exhibiting gradual recovery when exposed to extinction sessions (where the electric shock is removed and conditioned response becomes independent of the CS).
- Social learning in juvenile lemon sharks
- During the exposure phase observers paired with ‘demonstrator’ sharks performed a greater number of task-related behaviours than observers paired with ‘sham demonstrators’.
- When tested in isolation, observers previously paired with ‘demonstrator’ sharks completed a greater number of trials and made contact with the target significantly more often than observers previously paired with ‘sham demonstrators’. Such experience also tended to result in faster overall task performance.