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severity of conflict on the vertical axis, and population ratio on the horizontal axis. A scatterplot.
The relationship between population ratio (males aged 15 to 29 years per 100 males aged over 30 years) and conflict severity (death toll per million population per year) from 1980 to 1993 on a logarithmic scale. ( Adapted from Mesquida and Wiener 1995 )

severity on the vertical axis, and population ratio on the horizontal axis. A scatterplot.
The relationship between the 1989 population ratio (males aged 15 to 29 years per 100 males aged over 30 years) and severity of conflict (total death toll per million population) from 1989 to 1993 on a logarithmic scale. (Adapted from Mesquida and Wiener 1995)

How does testosterone affect aggression?

Although this chapter focuses on ultimate causes of human warfare, it is just as important to examine proximate causes in order to fully understand the nature of human aggression, such as the relationship between testosterone and aggression. Testosterone is the sex androgen believed to be responsible for masculine characteristics, and since females tend to have lower levels of testosterone as well as aggression, testosterone is assumed to have a causal relationship with aggressive behavior. In non-human animals, the hormone is known to be related to aggressiveness, and some studies have found a weak, positive relationship between testosterone levels and aggressiveness in humans as well (Book, Starzyk, and Quinsey 2001; Archer 1991). Testosterone levels have been shown to rise in males before engaging in competitive sports (Mazur and Booth 1998), and levels of testosterone can predict aggression in preschool boys (Sanchez-Martin, Fano, Ahedo, Cardas, Brain, and Azpiroz 2000). However, since studies in humans have largely been corrlational (Archer 1991), the exact nature of the relationship of testosterone in aggressive behavior in humans remains unclear.

Resource competition theory: why do males commit coalitionary violence?

The resource competition theory of coalitionary aggression posits that individual male participants involved in coalitionary acts of aggression gain fitness through an increased access to fitness-enhancing resources, as women prefer to mate with men who are able to provide themselves and potential offspring with these resources (Buss 1989). In this model, aggressive acts may increase fitness either when resources are under the control of a competitor, wherein an aggressor would increase fitness by gaining access to the resource, or when access to a resource is threatened by a competitor, wherein an aggressor avoids a fitness loss by limiting competition (Durham 1976; Buss and Shackelford 1997). Additionally, coalitions of men may also directly compete for access to women; for example, among the Yanomamo tribes have been recorded to raid neighboring groups and kidnap reproductive-aged females (Chagnon 1983 cited by Buss and Shackelford 1997).

In order to determine whether groups of males are more likely to compete over resources or females, researchers Manson and Wrangham hypothesized that when resources are easily monopolized, conflict will likely occur over these resources. However, in circumstances where essential resources are not easily monopolized, conflict will likely occur over females themselves. To ensure that resources are in fact related to reproductive fitness, the researchers also hypothesized that in situations where resources are easily monopolized, the accumulation of wealth will be associated with polygyny , whereas when resources are not easily monopolized, polygyny will correlate with other factors, such as social ranking or ability to defend family. To test this theory, the researchers analyzed the anthropological literature for ethnographic accounts of autonomous societies dependent on hunting and foraging that at least occasionally engaged in warfare. The researchers recorded whether the societies fought over resources or females, whether resources were easily monopolized, and whether polygyny and wealth were related. Results were consistent with predictions (see [link] and [link] ) (Manson and Wrangham 1991).

Questions & Answers

can someone help me with some logarithmic and exponential equations.
Jeffrey Reply
sure. what is your question?
ninjadapaul
20/(×-6^2)
Salomon
okay, so you have 6 raised to the power of 2. what is that part of your answer
ninjadapaul
I don't understand what the A with approx sign and the boxed x mean
ninjadapaul
it think it's written 20/(X-6)^2 so it's 20 divided by X-6 squared
Salomon
I'm not sure why it wrote it the other way
Salomon
I got X =-6
Salomon
ok. so take the square root of both sides, now you have plus or minus the square root of 20= x-6
ninjadapaul
oops. ignore that.
ninjadapaul
so you not have an equal sign anywhere in the original equation?
ninjadapaul
Commplementary angles
Idrissa Reply
hello
Sherica
im all ears I need to learn
Sherica
right! what he said ⤴⤴⤴
Tamia
what is a good calculator for all algebra; would a Casio fx 260 work with all algebra equations? please name the cheapest, thanks.
Kevin Reply
a perfect square v²+2v+_
Dearan Reply
kkk nice
Abdirahman Reply
algebra 2 Inequalities:If equation 2 = 0 it is an open set?
Kim Reply
or infinite solutions?
Kim
The answer is neither. The function, 2 = 0 cannot exist. Hence, the function is undefined.
Al
y=10×
Embra Reply
if |A| not equal to 0 and order of A is n prove that adj (adj A = |A|
Nancy Reply
rolling four fair dice and getting an even number an all four dice
ramon Reply
Kristine 2*2*2=8
Bridget Reply
Differences Between Laspeyres and Paasche Indices
Emedobi Reply
No. 7x -4y is simplified from 4x + (3y + 3x) -7y
Mary Reply
is it 3×y ?
Joan Reply
J, combine like terms 7x-4y
Bridget Reply
im not good at math so would this help me
Rachael Reply
yes
Asali
I'm not good at math so would you help me
Samantha
what is the problem that i will help you to self with?
Asali
how do you translate this in Algebraic Expressions
linda Reply
Need to simplify the expresin. 3/7 (x+y)-1/7 (x-1)=
Crystal Reply
. After 3 months on a diet, Lisa had lost 12% of her original weight. She lost 21 pounds. What was Lisa's original weight?
Chris Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
China
Cied
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
Porter
many many of nanotubes
Porter
what is the k.e before it land
Yasmin
what is the function of carbon nanotubes?
Cesar
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
AMJAD
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
AMJAD
what is system testing
AMJAD
what is the application of nanotechnology?
Stotaw
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
Azam
anybody can imagine what will be happen after 100 years from now in nano tech world
Prasenjit
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
Azam
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
Prasenjit
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
Damian
silver nanoparticles could handle the job?
Damian
not now but maybe in future only AgNP maybe any other nanomaterials
Azam
can nanotechnology change the direction of the face of the world
Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
Ali Reply
the Beer law works very well for dilute solutions but fails for very high concentrations. why?
bamidele Reply
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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