How groups travel is an interesting part of animal behavior. Elephants can form circles to protect younger members of the herd, while whales can coordinate enough to make spiral rings of bubbles to catch prey. New research has revealed why baboons travel in straight lines, and the answer is much more wholesome than you might think.
Wild chacma baboons (Papio ursinus) were recorded in Da Gama Park in South Africa’s Cape Peninsula. These baboons are known to travel in straight single file lines called progressions. However, while other research has tried to explore why the baboons might move in this way, nobody has come to a concrete conclusion.
Four reasons were explored by the team as possible reasons why the baboons might move in this way. One idea is that this is the best way to protect the younger or most vulnerable members of the troop. Others suggest they are simply following the group leader, competing for resources, or have patterns in these lines that relate to social bonds within the group itself.
Looking at 78 progressions over 36 days, the team found that the order of the baboons within the lines was not random. In fact, the team thinks that social bonds and hierarchy are the driving force behind the line order. The progressions that were studied lasted on average around 10 minutes, with the longest progression lasting over an hour.
“Surprisingly, the consistent order we see for the baboons we studied isn’t about avoiding danger like we see in prey animals when they position themselves in the middle of their social group, or for better access to food or water like we do in the movements of plains zebra. Instead, it’s driven by who they’re socially bonded with. They simply move with their friends, and this produces a consistent order,” Dr Andrew King, Associate Professor at Swansea University, said in a statement.
Most often the progressions occurred in the late afternoon or early evening when the group began to travel back to sleeping sites. Rather than having the dominant males in the group at the front, the more dominant members were actually found in the middle of the troop. This is in contrast to the idea that the troop are following a group leader who makes the decisions about where to go.
“In the baboon group we studied, the more socially connected, higher-ranking individuals usually walk in the middle of the group, while lower-ranking baboons are often out in front or at the rear. During these group movements – like heading to a familiar sleeping spot – it’s likely that the group already knows where they’re going. So, the baboons at the front aren’t really leading; they’re just out ahead,” continued King.
The team found repeatability in the travel order, suggesting that baboons like to hang out in familiar orders with their mates. Lower-ranked baboons were more likely to be at the front or back, strung out from the others since they have fewer close social relationships; whereas, higher-ranked baboons with a strong hierarchy were closer to other baboons near the middle of the line. These baboons were consistently more likely to be in the middle but had a greater variation in which baboons were next to them, reflecting the fact they have more social connections within the group.
In short, the baboons just want to hang out with their friends while they walk – and honestly, who can blame them?
The study is published in Behavioral Ecology.
Source Link: There Is A Very Particular Reason Why Baboons Travel In Straight Lines
