Awasthi, B. | Search bioRxiv

bioRxiv2022

MegaFeed: Global database of megaherbivores' feeding preferences

Terrestrial mammalian herbivores heavier than ~1000 kg, also known as megaherbivores, perform unique ecological functions due to their combination of heavy body mass, extended home ranges, abundant biomass consumption, and highly diverse diet. Megaherbivores can have substantial effects on ecosystem functioning, vegetation structure, and biogeochemical cycles. Elephants (family Elephantidae) and rhinoceros (family Rhinocerotidae) are two of the remaining megaherbivores that survived the late Pleistocene extinctions, but their populations have been globally declining in the last century. Feeding preferences are a key factor determining the influence of megaherbivores on ecosystems and plant communities; however, comprehensive and centralized data on megaherbivores food preferences are lacking. Here we present MegaFeed, an extensive dataset of megaherbivores feeding preferences across their distribution. This first version of MegaFeed here described contains more than 12,000 records of feeding preferences for the extant elephant species: Loxodonta africana (African savanna elephant), Loxodonta cyclotis (African Forest elephant), and Elephas maximus (Asian elephant). MegaFeed will contribute to a better understanding of the ecological functions of megaherbivores, evaluate the consequences of their decline, and guide rewilding and conservation initiatives such as habitat restoration and reduction of human-wildlife conflicts.

ecology↗

bioRxiv2019

Moving by thoughts alone? Amount of finger movement and pendulum length determine success in the Chevreul Pendulum Illusion

Hand-held pendulums can seemingly oscillate on their own, without perceived conscious control. This illusion, named after Chevreul, is likely a result of ideomotor movements. While this phenomenon was originally assumed to have a supernatural basis, it has been accepted for over 150 years that the movements are self-generated. However, until now, recordings of the small movements that create these oscillations has not been performed. In this study, we examined the mechanism that produces these significant involuntary oscillations using a motion capture system. We determined that the Chevreul pendulum illusion is produced when the fingers holding the pendulum generate an oscillating frequency close to the resonant frequency of the pendulum. At an appropriate frequency, very small driving movements of the arm are sufficient to produce relatively large pendulum motion. Further, subjects that tended to move their fingers more were more successful in producing the illusion.

neuroscience↗