why do we cry

the non-emotional reasons we have tears is to keep our eyes clean and hydrated .. so you would have tears in your eyes when there is a foreign element which enters your eyes .. thats the way the human body protects the eye ..

the other kind of crying is what babies do ... atleast the vocal part of the crying is related to the lack of communication skills of the baby .. also crying was a way to ensure that the baby can reach its parents in case they are separated (which i assume wasn't very uncommon when we were wild) 

now the more complicated kind of tears .. the one which we get when we get too emotional .. there is one evolutionary reason for the same.. its old people copying the babies .. most adults have an urge to show sympathy to anyone crying (because they associate crying with babies and adults are wired to take care of babies) .. so when attacked or under distress humans would start crying to mimic babies which increased their odds of being spared ..

why do guys masturbate

is there an evolutionary reason to this? first of all, its not just humans who masturbate.. there are bunch of animals who do it .. dogs hump all the time .. horses do it as well ..

now going into the possible reasons .. one reason which is proposed in general is that it is the process to get rid of old semen in the body to be replaced by freshly produced ones which would have higher odds to fertilise the egg ..

or may be this is our way of fighting evolution .. humans were sexually polygamous where in a male would mate with a group of females .. in the recent past we have moved from sexually polygamous to being socially monogamous .. and may be masturbating (by watching porn or fantasising about different women) is a way of men to stay faithful to their partners while satisfying their need to be sexually polygamous..

or may be the only relation of masturbation and evolution is that the former is the product of sexual urge and the latter needs sexual urge to succeed ..

skin colour and evolution

how was the skin colour of different races driven by evolution?

earliest sapiens (current humans) started from Africa .. Africa has ample amount of sunlight and given we never wore a lot of clothes (or had sunscreen) to protect ourselves from sun we needed melanin .. its a natural skin pigment which protects skin from UV radiation and hence cancer .. so we in Africa produced a lot of melanin to survive .. then when the sapiens moved to north in Europe the exposure to sun was much lower which lowered the need of melanin giving them a fairer skins over tens of thousands of years .. then the same europeans moved to south america via north america the melanin went up again giving them back the darker skin colour ..

why do older guys go for younger women

why do we see so many not-so-young men leaving their wives and families for young girls ..

as usual .. i would blame evolution instead of calling the guy a pervert .. all a guy wants (without him knowing) is to ensure that his gene goes on .. he wants to maximise the probability of having kids ..

there is a big difference between male and female fertility .. females reach their peak at the age of 20 and their fertility goes down very fast after the age of 35 .. same thing is applicable to males as well but the decline in fertility is not that pronounced .. this is also because the male just needs to fertilise a healthy egg but the female has to go though a much longer 9 month gestation period which requires her to be in top health conditions ..

so our ancestor males figured it out that if they want to maximize the probability of their gene's survival and have more babies they need to move to younger female partners once their current partners reach a not-so-fertile age of 40 and above .. this tendency of moving to younger girls has lived on deep inside the males long after till today .. its natural instinct that a guy in his 40s would get attracted to a girl in her 20s .. this is one of the reasons we as a specie have survived .. if it wasn't for this our chances of survival would have been much lower

why do guys like girls with big boobs and ass

the definition of sexy is surprisingly well defined all over the world .. it has been changing off late but still a girl with curves (big boobs small waist) is the most common standard for sexy

there is a hormone called progesterone which is vital for female pregnancy .. helps in maintaining menstrual cycles and supports gestations .. there is another hormone called estradiol which helps in development of sexual organs (supports vagina lining etc) ..  now it has been researched and found out that the the girls with a high ratio of boobs to waist would have as much as 3 times of these hormones than other girls .. 

us humans had obviously figured it long time back by trial and error .. the guys figured out that if he could find a mate with a high ratio of breast to waist, his odds of procreating would go up a lot .. this was learnt by human males over 100s and 1000s of generations and has become a part of the way guys think now without anyone having to tell them .. 

and thats why a guy would get attracted to a "hot girl" with big boobs / ass and small waist :)

why are most people right handed

humans are different from most other animals in this .. most of us (close to 90%) are right handed .. but is there any evolutionary reasoning

humans started using tools very long ago (the oldest stone tools found are 3.5 million years old !!) .. we started sharpening stones to make axes / hunting gears / hammers etc etc .. but such tools would have been a prized commodity to be used by a group or a family .. there would be less tools than users .. most of the tools worked better in one hand than the other (try asking a left handed guy to use your scissor and you would know), which means that it's more efficient for the group as a whole that everyone is better at using the same set of tools with one hand .. now i can't think why right would be preferred over left in evolution so i just assume it was 50:50 odds.. so more and more people became so that they could use the same set of tools which leaves us where we are now.. 

why do girls like guys with good bodies

what is it about the biceps and six-packs which has the girls drooling ?

humans started living in groups long time back when the work was divided between males and females .. males were the hunters / gatherers and females would stay back for foraging close to the camp and raising kids .. the strongest guy would get the biggest share of the hunt and therefore his wife (or wives) and kids would get the biggest share as well .. evolution dictates that the mother would want one thing more than anything else: her and her kids to survive .. if the mother is able to chose the strongest guy her odds are the best .. and this has lived in the female genes forever .. every time a girl sees biceps and six packs, it triggers her instinct of trying to get the guy to make babies with her :D

why do guys want to have sex with a lot of girls

guys are always seen as assholes who would do anything to get into a girls pants and as many pants as possible .. but why is that .. why is this massive urge that guys have to have sex ..

for any specie to survive they have to have offsprings .. for them to have offsprings they need to have sex .. it takes 9 months after the egg is fertilised for the baby to come in the world .. so the female is booked for 9 months once she's pregnant .. the guy on the other hand is still available to mate .. now assuming evolution works and it dictates that the best genes are passed on to the next generation the most efficient way of doing this is to get 1 out of say 10 males' genes to pass on with 10 female genes .. so 10 guys fight it out, 1 of them (the strongest gene) wins and then he gets to "spread his seed" to get to the next generation .. the males are hardwired deep down inside to win the race and have sex with as many girls as he possibly can .. this is how we survived in the past and it will take a lot of time to get over this hardwiring (the monogamy is a very recent phenomenon).

hope this helps some girls see a reason to forgive their boyfriends when they catch him sleeping with some other girl .. its not his fault .. its evolution !

the basic premise of evolution explains

for explaining any human behaviour there are many many factors and reasons .. i would just be focusing on the evolutionary reasons for explaining a particular behaviour / observation / characteristic.

the basic premise of evolution is that all the species including humans developed habits and traits to ensure their survival .. this instinct of survival which might not be relevant now still carries forward in our genes and dictates a lot of our behaviour till this age ..
we are constantly evolving .. physically and behaviourally .. i think the physical evolution is much slower .. but if we understand how where we were has determined where we are now .. we might be able to judge where we would be in the future ..

This blog

i like to think that a lot of things around us can be explained with evolution .. i googled but couldn't find one proper source of stuff explained by evolution ..  i keep reading about evolution around the net and connecting some dots myself every now and then .. i will try to post as many of them here as possible ..