Diet influences resource allocation in chemical defence in an aposematic moth
Data files
Feb 06, 2024 version files 28.26 KB
Abstract
For animals that synthesise their chemical compounds de novo, resources, particularly proteins, can influence investment in chemical defences and nitrogen-based wing colouration such as melanin. Competing for the same resources often leads to trade-offs in resource allocation. We manipulated protein availability in the larval diet of the wood tiger moth, Arctia plantaginis, to test how early life resource availability influences relevant life history traits, melanin production, and chemical defences. We expected higher dietary protein to result in more effective chemical defences in adult moths and a higher amount of melanin in the wings. According to the resource allocation hypothesis, we also expected individuals with less melanin to have more resources to allocate to chemical defences. We found that protein-deprived moths had a slower larval development, and their chemical defences were less unpalatable for bird predators, but the expression of melanin in their wings did not differ from that of moths raised on a high-protein diet. The amount of melanin in the wings, however, unexpectedly correlated positively with chemical defences. Our findings demonstrate that the resources available in early life have an important role in the efficacy of chemical defences, but melanin-based warning colours are less sensitive to resource variability than other fitness-related traits.
README: Diet influences resource allocation in chemical defence but not melanin synthesis in an aposematic moth
Melanin_BirdResponse.txt and LifeHistoryMales.txt are the raw data in a format that can be opened in Wordpad or Excel.
The Melanin_BirdResponse.txt file includes raw data for the predators' response to the thoracic fluid of Estonian male wood tiger moths and the measurement of the melanin amount in the same moths, while the LifeHistoryMales.txt is the measure of life-history traits of those Estonian male wood tiger moths
The headers of columns for the Melanin_BirdResponse.txt are defined below:
- birdID: ID individual of each bird
- sex: sex of the bird
- age: indicate whether the bird was Juvenile/Adult
- treatment: diet treatment of the individual moth
- idmoth: ID of individual moth
- family: the family of the moth
- colour:indicates the melanisation of the moth's hindwing classified by eyes
- Trial: trial (1,2,3,4). trial 1 and 4 were water and 2 and 3 were with the thoracic fluid
- tsee: time (in seconds) recorded when the bird see the bait (oat flake) with the thoracic fluid
- tapp: time (in seconds) recorded when the bird approach the bait (oat flake) with the thoracic fluid
- tattack: time (in seconds) recorded when the bird grab the bait (oat flake) with the thoracic fluid
- teat: time (in seconds) recorded when the bird starts to eat the bait (oat flake) with the thoracic fluid
- handltime: time (in seconds) recorded when the bird handle the bait (oat flake) with the thoracic fluid
- lateat: hesitation time (in seconds) measured as time in seconds from seeing the oat to pecking/eating the first oat
- propeat:Proportion of bait (oat flake) eaten in each trial
- pbw: beak cleaning a disgust behaviour measured as the number of bouts where the bird wiped its beak against a surface such as the perch (indicates as 0, if it didn't happen or 1 if it happen)
- nbw: number of times the bird beak wipes
- pw: drinking, indicates when bird drank water, which is a behaviour that can increase in response to distasteful food (indicates as 0, if it didn't happen or 1 if it happen)
- nw: number of time the bird drinks water
- tfinal:final time when the trial end (in seconds)
- tduration: duration time (in seconds) of the entire trial
- BlackCover: Melanin amount measured (as number of pixels)
'na' values: indicates values not available
The headers of columns for LifeHistoryMales.txt are defined below:
- MIR17: label indicated the year (2017)
- ID: ID of individual moth
- Family: family of the moth
- Individual_number: individual number of the moth
- treatment: diet treatment of the individual moth
- larva_date: date of the egg eclosion
- pupa_date: date of when the individual from larvae it becames pupae
- pupa_weight: weight of the pupae (mg)
- adult_date: date of the pupa eclosion to adult
- survival: whether the individual survived or not
- development_time_days: time in days to develop
- sex: sex of the moth
- BlackCover: Melanin amount measured (as number of pixels)
- N_volume: Volume of the thoracic fluid (chemical defences) (μl)
'na' values: indicates values not available