Why do we fish? At some point eons ago, our primarily fruit-eating ancestors put their hands in the water to catch and eat aquatic life, inadvertently supplementing their diet with nutrients that initiated a brain development process that eventually led to us. But how did this begin?
 |
| Chimpanzee fishing for crabs [Credit: Kathelijne Koops] |
Writing in the Journal of Human Evolution, the team describes year-round, fresh water crab-fishing behavior -- primarily among female and infant chimpanzees -- living in the rainforest of the Nimba Mountains in Guinea, West Africa.
 |
| Fresh-water crab [Credit: Kathelijne Koops] |
"Further, our findings suggest that aquatic fauna may have been a regular part of hominins' diets and not just a seasonal fallback food."
 |
| The Nimba Mountains in Guinea where chimpanzees call home [Credit: Kathelijne Koops] |
Crabbing, they learned, not only took place year-round -- without regard to season or fruit availability -- but intriguingly was negatively correlated with the chimps' consumption of ants, another diet staple. Mature males were the least likely to consume aquatic fauna.
Chimpanzees have a mainly vegetarian diet, but do occasionally eat meat. Researchers at the University
of Zurich have now shown for the first time that chimpanzees also eat crabs. In the rainforest
of Guinea, the researchers observed how chimpanzees regularly fish for crabs
[Credit: Kathelijne Koops]
The study further sheds light on our own evolution, by showing that fishing behaviors may not be restricted by habitat as initially assumed.
Chimpanzee mother fishing for freshwater crabs while her offspring practices
[Credit: Kyoto University/Kathelijne Koops]
"It's exciting to see a behavior like this that allows us to improve our understanding of what drove our ancestors to diversify their diet."
Source: Kyoto University [May 29, 2019]
No comments: