HIDE AND SEEK: AN EXPLORATION OF ANTIPREDATOR AND PREDATOR AVOIDANCE MECHANISMS IN ORTHOPODOMYIA SIGNIFERA IN RESPONSE TO PREDATION FROM TOXORHYNCHITES RUTILUS

<p>There have been many observations of larval <em>Orthopodomyia signifera</em> coexisting with the predator <em>Toxorhynchites rutilus.</em> There are three hypotheses that could explain how <em>Or. signifera</em> resists predation from <em>Tx. rutilus</em>. The first hypothesis states that larvae adapt behavioral changes that limit predation. The second hypothesis states thoracic setae serve as a physical defense that prevents <em>Tx. rutilus</em> from grasping <em>Or. signifera</em>. The third hypothesis states <em>Or. signifera </em>possess a chemical defense indicated by aposematic coloration. To test the first hypothesis larval <em>Or. signifera</em> were exposed to conspecific and heterospecific predation cues and their behavior was observed. Both cues caused <em>Or. signifera</em> to change their behavior, with conspecific cues causing the most stringent defensive behavior and heterospecific cues causing moderate defensive behavior. This led to the confirmation of the first hypothesis. To test the second hypothesis the rate of successful strikes of <em>Tx. rutilus</em> on <em>Or. signifera</em> and <em>Aedes albopictus</em> were compared. There was no significant difference in the successful strike rate of <em>Tx. rutilus</em> on <em>Or. signifera</em> and <em>Ae. albopictus </em>and the second hypothesis was rejected. For the third hypothesis the functional response of <em>Tx. rutilus</em> on <em>Ae. albopictu</em>s and <em>Or. signifera</em> when exposed to a natural and artificial diet was compared. Diet was not a factor, however, <em>Or. signifera</em> had significantly longer handling time and fewer 2^nd strikes in comparison with <em>Ae. albopictus</em>. The third hypothesis was inconclusive as the results could indicate a physical or chemical defense.</p>

Name thesis:degree_name

Master of Science (MS)

Level thesis:degree_level

Masters Thesis

Year dc:date.available

2023

Author dc:creator

• Dahlberg, Nathaniel

Contributors dc:contributor

• Donald Yee
• Jake Schaefer
• Miguel Acevedo

• Mosquito
• Ecology
• Entomology
• Predator
• Prey Predator Defense
• Chemical Defense
• Physical Defense
• Behavioral Defense
• Behavior and Ethology
• Biodiversity
• Terrestrial and Aquatic Ecology
• Zoology

Repository record dc:identifier

https://aquila.usm.edu/masters_theses/952

OAI identifier oai:identifier

oai:aquila.usm.edu:masters_theses-2025