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These conditions have created divergent optimum reproductive strategies between the sexes. Males are driven to mate as many times, and with as many females, as possible in order to maximize the number of eggs he fertilizes. Simultaneously, however, females seek to offset the disproportionate costs of reproduction by obtaining a paternal investment from the male, which can come in the form of food, protection, defense of resources, or other energetic expenditures. The female may select mates based on secondary sexual trait indicators of “good providers.” Inducing the male to bear a greater share of the reproductive burden allows the female to store resources for future offspring (reduces her parental investment) (Schneider and Lubin 1998).

Female selection for paternal investment may impose a suite of costs not directly associated with resource provision, such as elaborate male courtship costs (Schneider and Lubin 1998). In species of arachnids and insects, females often guard the ootheca before it hatches, but males do not directly provide parental care. Thus, parental investment and sexual conflict chiefly occur within the context of mating (Schneider and Fromhage 2005).

Life-history parameters such as the timing of sexual maturation and oviposition, expected number of matings, body size, maturity, and generation length are likely to influence the degree and outcome of intersexual conflict (Buskirk et al. 1984). Dynamics of functional morphology and ecology may also limit or enhance mating costs/benefits, impacting intersexual conflict (Andrade 2003).

Several hypotheses explain ways in which sexual cannibalism can occur by natural selection. This chapter first discusses the interpretation of sexual cannibalism as a case of paternal investment : females require substantial nutrients to produce their eggs, and extract food from the male’s own biomass. This “foraging strategy” hypothesis is based on experiments with mantises since male self-sacrifice drastically increases the reproductive yield of the female (Barry et al. 2008). Enhancing female fecundity improves the male’s direct fitness because he can pass on more of his genes through healthy offspring. This chapter also reviews corroborating evidence from redback spider males, who initiate their own cannibalism to maximize reproductive benefit in a hostile environment that opposes repeated mating (Andrade 1996). An outwardly brutal mating interaction may ultimately be adaptive for members of both sexes.

This chapter proceeds to examine the limitations of, and alternatives to, the above hypothesis. Many male spiders and mantises are not complicit in self-sacrifice, indicating that cannibalism is not adaptively favorable to males (Liske and Davis 1987; Wilder and Rypstra 2008). Additionally, sexual cannibalism is prominent in size dimorphic spider species, in which males are too small to substantively feed females. These observations give rise to claims that cannibalism in the context of mating is actually a non-sexual, predator-prey interaction (Wilder and Rypstra 2008b). Alternatively, a sexual selection hypothesis suggests that females discriminately eliminate undesirable mates by devouring them (Elgar and Nash 1988). Overall, the examination of sexual cannibalism reveals the variable influences of species morphology and environmental conditions on a behavior’s evolutionary significance. Also, since both reproductive and mortality considerations are inherent in sexual cannibalism, examining its adaptive value offers intriguing insight into the fitness dynamics of sexual interactions

Questions & Answers

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 to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
How can I make nanorobot?
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
how can I make nanorobot?
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Mockingbird tales: readings in animal behavior. OpenStax CNX. Jan 12, 2011 Download for free at http://cnx.org/content/col11211/1.5
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