<< Chapter < Page Chapter >> Page >

Notice what happens to the equation when it is certain that the male will be cannibalized (ENC=1 and C=1): the right side of the inequality becomes zero. Any value of A/P greater than zero (that is, any increase in number of offspring due to sexual cannibalism) thus conveys a selective advantage to sexual cannibalism (Buskirk et al. 1984). This relatively simple model organizes the costs and benefits of male complicity into comparable mathematical terms, describing the conditions by which sexual cannibalism favors male fitness.

The female perspective

Newman and Elgar supplement Buskirk’s hypothesis with an economic model from the female perspective, drawing on evidence from the orb-weaving spider. Specifically, these researchers address pre-copulatory cannibalism, in which the female consumes the male before sperm transfer is complete (post-copulatory cannibalism is assumed to never harm the female, unless the species raises young and requires future male aid). The mathematical description of Newman and Elgar involves complex dynamic programming, and will not be detailed here. However, it essentially illustrates that females are more likely to engage in pre-copulatory cannibalism if they can encounter several males during a season and have both a low and inconsistent food intake rate from non-mate sources (Newman and Elgar 1991). This model resonates well with the foraging strategy hypothesis, which also emphasizes the nutritional utility of sexual cannibalism for females.

The intersection of the two economic models illustrates the possibility for intersexual conflict in sexual cannibalism. There is a discrepancy between parameters of fitness benefit from the female and male perspectives (Newman and Elgar 1991). For example, consider a mating season in which males encounter many females, and females also frequently meet males. In these conditions, males will incur high costs from sexual cannibalism because they forgo ample mating opportunities. Simultaneously, females will be more inclined to consume mates before copulation because they have many chances to accept sperm later. The discord between male and female perspectives drives some level of conflict of interest in mating interactions. Depending on ecological conditions and species traits, members of the opposite sex experience different costs and benefits that determine the extent to which cannibalism is adaptively favorable.

Applications of economic models to mantises and spiders

The economic models of Buskirk; and Newman and Elgar help explain previous observations, including male mantises’ non-cooperation in sexual cannibalism. For most mantises males, the likelihood of finding a second mate is high, which increases the cost of self-sacrifice by Buskirk’s model. Even if the male’s biomass improves female fecundity, the resulting viability of the male’s offspring must not be great enough to overcome the cost to his future mating opportunity. (Gemeno and Claramunt 2006). Sexual cannibalism in mantises must be adaptive solely from the female perspective (conflict of interest).

Questions & Answers

what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
yes that's correct
I think
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
Privacy Information Security Software Version 1.1a
Got questions? Join the online conversation and get instant answers!
Jobilize.com Reply

Get the best Algebra and trigonometry course in your pocket!

Source:  OpenStax, Mockingbird tales: readings in animal behavior. OpenStax CNX. Jan 12, 2011 Download for free at http://cnx.org/content/col11211/1.5
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Mockingbird tales: readings in animal behavior' conversation and receive update notifications?