In this bachelor thesis the behavior of burying beetles (Nicrophorus vespilloides) was further investigated through a detailed behavioral study. In this study fighting videos between N. vespilloides residents (females with larvae and a carcass) and intruders (females without larvae and a carcass) were evaluated. Half of the residents were treated with a FMRFamide solution and the other half there treated with a saline solution (control group). The FMRFamide treatment results in a more aggressive behavior in the females. This reaffirm the role of FMRFamide as an agent which has an influence in triggering aggressive behavior in burying beetles.
Aggressive behavior is widespread among animals and crucial for survival and passing on their genes. Aggressive behavior therefore mostly occurs during competition for resources like mating partners, nutrition and territory. Hence the burying beetle Nicrophorus vespilloides also use aggressive behavior to protect its brood. In previous studies the JH III (Juvenile Hormone III) titer in burying beetles could be identified to be causal for brooding behavior and therefore also causal for the increased aggression during breeding time. The regulation of JH titer in insects is unclear to this moment. Peptides with a tetrapeptic ending like FMRFamide have been suggested in the past to play a role in the regulation. Hence the effect of FMRFamide as a potential JH releasing factor also was investigated in burying beetles. This effect could not be confirmed to this date however a correlation between aggression and FMRFamide was found.
Table of Contents
1. Abstract
2. Introduction
3. Material and methods
4. Results
4.1 Duration of behaviors
4.2 Chronological occurrence of behaviors
4.2.1 Comparison of the behaviors occurring in the different treatment groups
4.2.2 Separate analysis of occurrence in each individual behavior
5. Discussion
Research Objectives and Key Topics
This thesis investigates the influence of the neuropeptide FMRFamide on the aggressive behavior of the burying beetle Nicrophorus vespilloides. By conducting a detailed behavioral analysis of interactions between resident females and intruders, the research aims to clarify whether FMRFamide acts as an agent that triggers or modulates aggressive responses, specifically examining changes in behavior duration and chronological succession patterns.
- Analysis of aggressive and non-aggressive behavioral patterns in N. vespilloides.
- Evaluation of the impact of FMRFamide treatment on resident female behavior.
- Comparison of behavioral durations between treated and control groups.
- Investigation of the chronological order (succession) of observed behaviors during fighting.
- Assessment of the role of FMRFamide in potentially reinforcing aggressive tendencies.
Excerpt from the Book
3. Material and methods
This bachelor thesis founds on the master Thesis “Influence of RFamide on the aggressive behavior of female burying beetle – A behavioral, immunocytochemical and pharmacological study” written by Annika Verena Lipp in 2015. For further details, please refer to that thesis. The thesis wanted to differentiate the aggressive behaviors which are shown by Nicrophorus vespilloides during the defense of their larvae. Furthermore, it wanted to show potential differences between the behavior on day 4 and 7 of the breeding cycle as if FMRFamide have an influence on aggressive behavior in resident females.
To achieve this, the nest defenders were separated in a manipulated group, which was treated with 30 µl RFamide dissolved in saline with a concentration of 0.001 g/l on the 4. and 7. day after breeding start and a control group which was treated with 30 µl mosquito saline on the same days.
Videos which were recorded originally for the mentioned master thesis by Annika Verena Lipp were further analyzed by me. Each video showing a 10 minutes long fight between a defender (manipulated group/control group) and an intruder female of N. vespilloides in a fighting arena on day 4 and 7 after breeding start.
Summary of Chapters
1. Abstract: Provides a concise overview of the study's motivation regarding FMRFamide's role in insect aggression and summarizes the finding that FMRFamide treatment results in more aggressive behavior in burying beetles.
2. Introduction: Outlines the biological background of N. vespilloides, focusing on their parental care, resource competition, and the physiological link between Juvenile Hormone III levels and aggressive state.
3. Material and methods: Details the experimental setup, including the application of FMRFamide or saline to resident females and the methodology used to analyze 10-minute fighting videos.
4. Results: Presents the quantitative data regarding the duration and chronological occurrence of specific behaviors, identifying significant differences in fighting patterns between treated and untreated groups.
5. Discussion: Interprets the findings, suggesting that FMRFamide reinforces aggressive behavior, and acknowledges methodological limitations while proposing future research directions regarding insect communication.
Keywords
Nicrophorus vespilloides, burying beetles, FMRFamide, aggressive behavior, Juvenile Hormone III, parental care, behavioral analysis, ethology, entomology, neurobiology, fighting interaction, intruder defense, chemical communication, reproductive behavior.
Frequently Asked Questions
What is the core focus of this bachelor thesis?
The thesis focuses on examining the influence of the peptide FMRFamide on the aggressive behavior of the burying beetle Nicrophorus vespilloides during interactions with intruders.
What are the primary themes investigated?
The study explores the link between FMRFamide treatment and increased aggression, the duration of specific aggressive and non-aggressive behaviors, and the chronological order of these behaviors during conflict.
What is the central research question?
The research asks how the administration of FMRFamide changes the duration of specific behaviors and how it influences the succession pattern of aggressive displays in female burying beetles.
Which scientific methodology was utilized?
The author conducted a detailed behavioral study by analyzing 10-minute video recordings of fights between resident beetles and intruders, using statistical tests such as the Wilcoxon Rank Sum and Signed Rank tests.
What does the main body of the work cover?
The main body covers the experimental design, the categorization of observed behaviors (such as biting, entanglement, and stridulation), the statistical comparison of behavior durations, and the analysis of behavioral chronologies on breeding days 4 and 7.
How would you characterize the work using keywords?
Key terms include Nicrophorus vespilloides, aggressive behavior, FMRFamide, ethology, behavioral study, and insect neurobiology.
Did the study confirm that FMRFamide increases aggression?
Yes, the results indicate that FMRFamide treatment leads to more aggressive behavior in female burying beetles, evidenced by significant differences in the timing and duration of aggressive actions.
How does stridulation function within these interactions?
Stridulation is identified as a potential communication tool that showed the highest frequency in treated residents and intruders on day 7, suggesting it may serve as an interactive signaling mechanism during conflict.
- Arbeit zitieren
- Daniel Höfer (Autor:in), 2016, Behavioral Study of Female Burying Beetles. Influences on Aggressive Behavior, München, GRIN Verlag, https://www.grin.com/document/924862
