As we’ve discussed previously, not all fluid-like behavior occurs within a literal fluid. Many groups of organisms — humans included — behave like a fluid en masse. Herds of sheep are a fantastic example of this, and now researchers have actually analyzed footage of sheep as a fluid!
The authors find strong evidence for emergent collective behavior among the sheep, as well as a tendency for the flock to minimize its perimeter. In other words, even though the sheep do not physically exert an attractive force on one another, they behave as though the flock has surface tension! For a herd animal, this behavior makes sense since it minimizes the exposure of individuals to predators. (Image credit: top image – S. Carter, drone footage – M. Bircham; research credit: M. de Marcken and R. Sarfati; submitted by Kam-Yung Soh)
ETA: Thanks to commenter gib for finding the original author of the drone footage!
gib
the drone footage is by hunter Matthew Bircham, from Wellington. It has been sped up.
https://www.stuff.co.nz/business/farming/102784544/drone-footage-of-sheep-like-schooling-fish-mesmerises-social-media
Drone footage shows sheep ‘like schooling fish’
EMILY HEYWARD16:08, Apr 03 2018
Bircham said the farm dogs were herding about 3500 ewes at the farm between Blenheim and Hanmer Springs last week.
The video, posted on the NZ Farming Facebook page, had been shared more than 7000 times and had more than 650 comments.
Nicole Sharp
Thanks so much for sharing! I’ve updated the post’s credits accordingly.