Luring cannibal: dishonest sexual signalling in the springbok mantis
Data files
Jul 09, 2025 version files 44.05 KB
-
LC_-_control_choice_trials.csv
2.40 KB
-
LC_-_fecundity_test_cann_vs_no_cann.csv
2.62 KB
-
LC_-_fecundity_test_low_vs_high.csv
2.07 KB
-
LC_-_mate_choice_trials.csv
7.88 KB
-
LC_-_mating_trials.csv
14.18 KB
-
README.md
14.90 KB
Abstract
Sexual signals that attract the opposite sex are typically honest indicators of quality. However, sexually antagonistic selection can favour dishonest signals if poor quality members of the signalling sex can improve their own fitness at a cost to the opposite sex by conveying deceptive information in their signals. Here, using the sexually cannibalistic mantis Miomantis caffra, we found evidence that females in low body condition use sexual deception to exploit males as prey. Females of high condition produced 97% heavier oothecae than low-condition females, indicating that high-condition females were the optimal choice for males. However, in a simultaneous mate choice experiment using a T-maze olfactometer, males chose the pheromonal signals of low-condition females twice as often as those of high-condition females, indicating that female pheromonal attractiveness did not match female quality. In subsequent mating experiments, low-condition females attacked males 3 times more frequently and cannibalised them 4 times more often than high-condition females did. Cannibalism provided significant material benefits for females of low condition, since oothecae produced by these females were 52% heavier when they cannibalised a male compared to when they did not. These results strongly suggest that low-quality females attract males dishonestly with their pheromones to boost fecundity through sexual cannibalism. Such deception could be widespread in sexually cannibalistic systems, especially if pheromone production is cheap, food limitation is common, and males represent a substantial meal for hungry females.
Dataset DOI: 10.5061/dryad.pg4f4qs2h
General information
Author information:
A. Lead author contact information:
Name: Laura Knapwerth
Email: l.knapwerth@t-online.de
Institution: Universität Hamburg
B. Co-author contact information:
Name: Nathan W. Burke
Email: nathwilliamb@runbox.com
Institution: Universität Hamburg
Date of data collection:
November 2022 to July 2024
Geographic location of data collection:
Hamburg, Germany
DATA & FILE OVERVIEW
1. File List:
Data is contained in five files:
A. LC_-_mate_choice_trials.csv
B. LC_-_control_choice_trials.csv
C. LC_-_mating_trials.csv
D. LC_-_fecundity_test_cann_vs_no_cann.csv
E. LC_-_fecundity_test_low_vs_high.csv
DATA-SPECIFIC INFORMATION FOR:
A. LC_-_mate_choice_trials.csv
1. Number of variables:
30
2. Number of cases/rows:
34 (one row per successful trial)
3. Variable List:
A. 'trial.number' (categorical): Replicate-level identifier for mate choice trials (i.e., the numerical order in which trials were conducted) (34 levels: 1 to 34)
B. 'trial.date' (date): The date that trials took place
C. 'female.low.id' (categorical): Identifier for females of low condition (34 levels)
D. 'female.low.length' (numerical): The length of the prothorax of low-condition females at adulthood (in mm)
E. 'female.low.weight' (numerical): Weight of females of low condition (in g), measured at the start of mate choice trials
F. 'female.low.condition' (numerical): Condition score of females of low condition, calculated as the residuals of the linear regression of the natural logarithm of 'female.low.weight' and the natural logarithm of 'female.low.length'
G. 'female.low.moult.date' (date): The date that low-condition females moulted to adulthood
H. 'female.low.age' (integer): The age of low-condition females at the start of mate choice trials (i.e., number of days from final moult to trial date)
I. 'female.high.id' (categorical): Identifier for females of high condition (34 levels)
J. 'female.high.length' (numerical): The length of the prothorax of high-condition females at adulthood (in mm)
K. 'female.high.weight' (numerical): Weight of females of high condition (in g), measured at the start of mate choice trials
L. 'female.high.condition' (numerical): Condition score of females of high condition, calculated as the residuals of the linear regression of the natural logarithm of 'female.high.weight' and the natural logarithm of 'female.high.length'
M. 'female.high.moult.date' (date): The date that high-condition females moulted to adulthood
N. 'female.high.age' (integer): The age of high-condition females at the start of mate choice trials (i.e., number of days from final moult to trial date)
O. 'mean.female.length' (numerical): Mean prothorax length (in mm) of high- and low-condition female pairs used in each trial
P. 'female.length.diff' (numerical): The difference in length (in mm) between low- and high-condition female pairs used in each trial, as an absolute value
Q. 'mean.female.age' (numerical): Mean age (in days) of low- and high-condition female pairs used in each trial
R. 'female.age.diff' (integer): The difference in age (in days) between low- and high-condition female pairs used in each trial
S. 'male.id' (categorical): Identifier for males (34 levels)
T. 'male.length' (numerical): The length of the male prothorax at adulthood (in mm)
U. 'male.weight' (numerical): Male weight (in g), measured at the start of mate choice trials
V. 'male.condition' (numerical): Condition score of males, calculated as the residuals of the linear regression of the natural logarithm of 'male.weight' and the natural logarithm of 'male.length'
W. 'male.moult.date' (date): The date that males moulted to adulthood
X. 'male.age' (integer): The age of males at the start of mate choice trials (i.e., number of days from final moult to trial date)
Y. 'starting.time.hours' (integer): The time that trials started (in hours, in 24h time)
Z. 'trial.duration.secs' (integer): The amount of time (in secs) that males took to choose a female by entering one of the arms of the T-maze
AA. 'choice.side' (categorical): The arm of the T-maze that males entered when choosing the pheromonal signal of a female (two levels: ‘left' and 'right')
AB. 'choice.condition' (categorical): The condition of the female that the male chose (two levels: 'low' and 'high')
AC. 'choice.value' (logical): Whether males chose females of low condition (scored as 1) versus high condition (scored as 0)
AD. 'trial' (categorical): Whether females were present for the trial (one level: 'females.present')
B. LC_-_control_choice_trials.csv
1. Number of variables:
13
2. Number of cases/rows:
20 (one row per successful trial)
3. Variable List:
A. 'trial.number' (categorical): Replicate-level identifier for mate choice trials (i.e., the numerical order in which trials were conducted) (20 levels: 1 to 20)
B. 'trial.date' (date): The date that trials took place
C. 'male.id' (categorical): Identifier for males (20 levels)
D. 'male.length' (numerical): The length of the male prothorax at adulthood (in mm)
E. 'male.weight' (numerical): Male weight (in g), measured at the start of mate choice trials
F. 'male.condition' (numerical): Condition score of males, calculated as the residuals of the linear regression of the natural logarithm of 'male.weight' and the natural logarithm of 'male.length'
G. 'male.moult.date' (date): The date that males moulted to adulthood
H. 'male.age' (integer): The age of males at the start of mate choice trials (i.e., number of days from final moult to trial date)
I. 'starting.time.hours' (integer): The time that trials started (in hours, in 24h time)
J. 'trial.duration.secs' (integer): The amount of time (in secs) that males took to enter one of the arms of the T-maze
K. 'choice.side' (categorical): The arm of the T-maze that males entered (two levels: ‘left' and 'right')
L. 'choice.left' (logical): Whether males chose the left arm (scored as 1) or the right arm (scored as 0)
M. 'trial' (categorical): Whether females were present for the trial (one level: 'females.absent')
C. LC_-_mating_trials.csv
1. Number of variables:
33
2. Number of cases/rows:
63 (one row per male-female pairing)
3. Variable List:
A. 'trial.number' (categorical): Replicate-level identifier for mating trials (63 levels: 1 to 63)
B. 'trial.date' (categorical): The date that trials started, i.e., the experimental block (3 levels: '2023-01-16', '2023-01-24', '2023-01-27')
C. 'treatment' (categorical): The condition treatment that females belonged to (2 levels: 'low' and 'high')
D. 'female.id' (categorical): Identifier for females (63 levels)
E. 'female.length' (numerical): The length of the prothorax of females at adulthood (in mm)
F. 'female.weight' (numerical): Weight of females (in g), measured at the start of mate choice trials
G. 'female.condition' (numerical): Condition score of females, calculated as the residuals of the linear regression of the natural logarithm of 'female.weight' and the natural logarithm of 'female.length'
H. 'female.moult.date' (date): The date that females moulted to adulthood
I. 'female.age' (integer): The age of females at the start of mating trials (i.e., number of days from final moult to trial date)
J. 'male.id' (categorical): Identifier for males (63 levels)
K. 'male.length' (numerical): The length of the male prothorax at adulthood (in mm)
L. 'male.weight' (numerical): Male weight (in g), measured at the start of mating trials
M. 'male.condition' (numerical): Condition score of males, calculated as the residuals of the linear regression of the natural logarithm of 'male.weight' and the natural logarithm of 'male.length'
N. 'male.moult.date' (date): The date that males moulted to adulthood
O. 'male.age' (integer): The age of males at the start of mating trials (i.e., number of days from final moult to trial date)
P. 'trial.duration.in.hours' (numerical): The amount of time (in hours) that males spent paired with females in mating trials
Q. 'trial.duration.in.secs' (numerical): The amount of time (in secs) that males spent paired with females in mating trials
R. 'female.attacks' (integer): The number of times females attacked males
S. 'mating.binary' (logical): Whether mating took place (scored as 1) or not (scored as 0)
T. 'cannibalism.binary' (logical): Whether cannibalism occurred (scored as 1) or not (scored as 0)
U. 'time.from.m.to.c.hours' (numerical): For cases where cannibalism occurred after mating, the amount of time (in hours) that elapsed from the cessation of (the first) mating (i.e., when pairs visibly separated) to the onset of cannibalism (i.e., when females successfully grabbed hold of males and started eating them)
V. 'time.of.mating.hours' (numerical): The point of time in the trial (in hours) that the first mating ceased
W. 'time.of.cannibalism.hours' (numerical): The point of time in the trial (in hours) that cannibalism took place
X. 'mating.and.cannibalism' (logical): Whether both mating and cannibalism occurred (scored as 1) or only mating occurred (scored as 0)
Y. 'attacks.before.mating.interaction.binary' (logical): For cases where mating occurred, whether the female attacked the male before the start of the interaction in which (the first) mating occurred (scored as 1) or not (scored as 0)
Z. 'attacks.during.mating.interaction.binary' (logical): For cases where mating occurred, whether the female attacked the male during the interaction in which (the first) mating occurred (scored as 1) or not (scored as 0)
AA. 'attacks.after.mating.interaction.binary' (logical): For cases where mating occurred, whether the female attacked the male after the cessation of the interaction in which (the first) mating occurred (scored as 1) or not (scored as 0)
AB. 'number.of.interactions' (integer): The total number of male-female interactions during the mating trial, with an interaction defined as a discrete event/time period of physical contact between male and female that ends with physical separation of the pair
AC. 'mating.interaction.number' (integer): For cases where mating occurred, the chronological number of the interaction in which the first mating occurred
AD. 'second.mating.interaction.number' (integer): For cases where mating occurred a second time, the chronological number of the interaction in which the second mating occurred
AE. 'third.mating.interaction.number' (integer): For cases where mating occurred a third time, the chronological number of the interaction in which the third mating occurred
AF. 'cannibalism.interaction.number' (integer): For cases where cannibalism occurred, the chronological number of the interaction in which cannibalism occurred
AG. 'first.mating.duration.hours' (numerical): The duration of the (first) mating in hours during which males copulated with females
4. Note:
Variables Y, Z, AA, AB, AC, AD, AE, and AF were only used for supplementary calculations, plots, and analyses; variable AG was not used for any analyses
D. LC_-_fecundity_test_cann_vs_no_cann.csv
1. Number of variables:
17
2. Number of cases/rows:
19 (one row per female)
3. Variable List:
A. 'treatment' (categorical): The condition treatment that females belonged to (two levels: 'low' and 'high')
B. 'female.id' (categorical): Replicate-level identifier for females (19 levels)
C. 'female.length' (numerical): The length of the female prothorax at adulthood (in mm)
D. 'female.weight' (numerical): Female body weight at the start of the mating trial (in g)
E. 'female.condition' (numerical): Condition score of females, calculated as the residuals of the linear regression of the natural logarithm of 'female.weight' and the natural logarithm of 'female.length'
F. 'female.age' (integer): Female age (i.e., number of days from final moult to start of the mating trial)
G. 'male.id' (categorical): Replicate-level identifier for males (19 levels)
H. 'male.length' (numerical): The length of the male prothorax at adulthood (in mm)
I. 'male.weight' (numerical): Male body weight at the start of the mating trial (in g)
J. 'male.condition' (numerical): Condition score of males, calculated as the residuals of the linear regression of the natural logarithm of 'male.weight' and the natural logarithm of 'male.length'
K. 'male.age' (integer): Male age (i.e., number of days from final moult to start of the mating trial)
L. 'mating' (logical): Whether females mated (scored as 1) or not (scored as 0)
M. 'first.mating.duration.hours' (numerical): The duration of the (first) mating in hours during which males copulated with females
N. 'cannibalism' (logical): Whether females cannibalised (scored as 1) or not (scored as 0)
O. 'first.ootheca.weight' (numerical): The weight of the first ootheca (in g), measured two weeks after oviposition
P. 'second.ootheca.weight' (numerical): The weight of the second ootheca (in g), measured two weeks after oviposition
Q. 'total.ootheca.weight' (numerical): The total weight of the first and second ootheca (in g)
4. Note:
Variable M was only used for a supplementary calculation and analysis
E. LC_-_fecundity_test_low_vs_high.csv
1. Number of variables:
8
2. Number of cases/rows:
29 (one row per female)
3. Variable List:
A. 'treatment' (categorical): The condition treatment that females belonged to (two levels: 'low' and 'high')
B. 'female.id' (categorical): Replicate-level identifier for females (29 levels)
C. 'female.length' (numerical): The length of the female prothorax at adulthood (in mm)
D. 'female.weight' (numerical): Female body weight (in g), measured 3.5 weeks into the high and low feeding regimes
E. 'weighing.date' (date): The date that females were weighed
F. 'female.condition' (numerical): Condition score of females, calculated as the residuals of the linear regression of the natural logarithm of 'female.weight' and the natural logarithm of 'female.length'
G. 'age.at.allocation' (integer): Female age at feeding regime allocation (i.e., number of days from last moult to feeding allocation)
F. 'first.ootheca.weight' (numerical): Weight of the first ootheca (in g), measured two weeks after oviposition
We conducted a series of laboratory experiments to investigate whether hungry (low-condition) females of the sexually cannibalistic springbok mantis, Miomantis caffra, deceive males with their pheromonal signals to reap the material benefits of cannibalising them. We used a T-maze olfactometer to test whether males preferred the pheromones of high- or low-condition females. We also performed mating trials to assess whether females of high or low condition were more or less aggressive and cannibalistic toward males. Finally, we collected measurements on the difference in fecundity between high- and low-condition females, as well as the effect of cannibalism on the fecundity of low-condition females.