The Dung Beetle Dance: The role of visual cues in dung beetle orientation behavior
(2014) BIOP26 20132Degree Projects in Biology
- Abstract
- Popular science summary:
The Dance of A Straight Shooter
When a hungry dung beetle finds a dung pile, it soon starts forming a ball, which it will later roll away and eat in peace. As beetles are not very keen on making balls themselves, they will try to steal the balls of others. In order for a beetle to safely keep its food, it needs to get its ball as far away from the dung pat in the fastest manner possible. The best way to do this is to roll in a straight line. And this is exactly what the beetle does. But how does it do it?
Before the beetle rolls away from the pat, it climbs on top of its ball and performs a little dance. It rotates around its own axis, and every now and then, in the midst of the dance, it stops for short... (More) - Popular science summary:
The Dance of A Straight Shooter
When a hungry dung beetle finds a dung pile, it soon starts forming a ball, which it will later roll away and eat in peace. As beetles are not very keen on making balls themselves, they will try to steal the balls of others. In order for a beetle to safely keep its food, it needs to get its ball as far away from the dung pat in the fastest manner possible. The best way to do this is to roll in a straight line. And this is exactly what the beetle does. But how does it do it?
Before the beetle rolls away from the pat, it climbs on top of its ball and performs a little dance. It rotates around its own axis, and every now and then, in the midst of the dance, it stops for short pauses. It is thought that the beetles use their dance to set their rolling direction and to keep rolling in this direction if their straight-line path is disturbed. It has recently been suggested that the dance is visually based and that the beetles take a mental picture, a snapshot, of the sky when they are dancing. As the dance is believed to be influenced by what the beetle sees, it should look different depending on what visual scene is presented to the beetle. I tested this hypothesis by allowing the dung beetle Scarabaeus (Kheper) lamarcki to dance under different conditions where I, in some way, modified the visual input.
First, the beetles were allowed to dance in an environment were they did not have any readable visual cues. The results were that the beetle rotated more and took more pauses in its dance, compared to a dance of the same beetle when visual cues were present.
Second, to see if the beetle’s dance was affected when changing the location of a visual cue, the beetle was allowed to dance with a readable visual cue present. The location of this cue was then changed. The dance was not affected by the change in location of the cue.
As the number of pauses and total rotation of the beetle of the dance does differ when the beetle is lacking visual cues, we can conclude that it is a visually guided behavior. From my results, I suggest that, when the beetle dances, it scans the environment for visual information and when it then pauses, it takes a visual snapshot of the surroundings. As it then starts to roll, the beetle constantly re-matches its current view of the world with its stored view, making sure that it does not stray off course and risk bumping into the dung pat again. If the beetle is presented with clear, readable cues it will have sufficient amount of information to keep a straight rolling direction, no matter the location of the cue. However, if the beetle is presented with a condition in which there are no, or very few, readable cues available, it will have to scan more thoroughly, to gather enough information to help it roll straight. Understanding the orientation dance provides us with important clues on how animals like these can –despite their small brain- use visual compass cues to orient. Understanding this, we might be able to apply this knowledge in a practical way, creating better compasses and orientation tools than we have today.
Advisor: Emily Baird
Master´s Degree Project 60 credits in Sensory Biology, 2014
Department of Biology, Lund University (Less) - Abstract
- Abstract
When a dung beetle has arrived at a dung pat, it soon starts to form a ball, which it will later roll away in a straight line. Rolling in a straight line ensures that the beetle will never risk rolling back to the fierce competition at the pat, thus eliminating the chance of getting its ball stolen by others. Before rolling out from the pat, the beetle performs an orientation dance on top of the ball. This dance is believed to aid in establishing and keeping a straight roll bearing. Here, I test the hypothesis that dung beetles take visual snapshots of compass cues, allowing them to both set a roll bearing and to relocate this bearing after a disturbance. If the dance is visually based, it should be affected when visual compass... (More) - Abstract
When a dung beetle has arrived at a dung pat, it soon starts to form a ball, which it will later roll away in a straight line. Rolling in a straight line ensures that the beetle will never risk rolling back to the fierce competition at the pat, thus eliminating the chance of getting its ball stolen by others. Before rolling out from the pat, the beetle performs an orientation dance on top of the ball. This dance is believed to aid in establishing and keeping a straight roll bearing. Here, I test the hypothesis that dung beetles take visual snapshots of compass cues, allowing them to both set a roll bearing and to relocate this bearing after a disturbance. If the dance is visually based, it should be affected when visual compass information is removed or modified. Additionally, I predict that the duration of the dance will be longer when visual cues are lacking or are unreliable. My results indicate that the duration of the dance increases when there is a lack, or insufficient amount of visual compass cues. I conclude that the dance is not visually based, but visually regulated, as the beetles also dance in conditions where no visual input is present. (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/student-papers/record/4466562
- author
- Khaldy, Lana
- supervisor
-
- Emily Baird LU
- organization
- course
- BIOP26 20132
- year
- 2014
- type
- H2 - Master's Degree (Two Years)
- subject
- language
- English
- id
- 4466562
- date added to LUP
- 2014-06-16 13:41:37
- date last changed
- 2014-06-16 13:41:37
@misc{4466562,
abstract = {{Abstract
When a dung beetle has arrived at a dung pat, it soon starts to form a ball, which it will later roll away in a straight line. Rolling in a straight line ensures that the beetle will never risk rolling back to the fierce competition at the pat, thus eliminating the chance of getting its ball stolen by others. Before rolling out from the pat, the beetle performs an orientation dance on top of the ball. This dance is believed to aid in establishing and keeping a straight roll bearing. Here, I test the hypothesis that dung beetles take visual snapshots of compass cues, allowing them to both set a roll bearing and to relocate this bearing after a disturbance. If the dance is visually based, it should be affected when visual compass information is removed or modified. Additionally, I predict that the duration of the dance will be longer when visual cues are lacking or are unreliable. My results indicate that the duration of the dance increases when there is a lack, or insufficient amount of visual compass cues. I conclude that the dance is not visually based, but visually regulated, as the beetles also dance in conditions where no visual input is present.}},
author = {{Khaldy, Lana}},
language = {{eng}},
note = {{Student Paper}},
title = {{The Dung Beetle Dance: The role of visual cues in dung beetle orientation behavior}},
year = {{2014}},
}