Why are humans always in heat?


Non native speaker 🙃.

Are we the unique specie that is always horny or there are others?

Also why the arrive of the “horniess” is that early, 11.17 yo for males and 12.6 yo for females (Means from this paper: Timing of Puberty and Sexuality in Men and Women by Ostovich & Sabini , 2005) I mean this totally make sense for us boys, if you star having sex soon probably you will have more descendants, but this don’t have any benefits (beside is a funny feeling…) for females, Is not the twenties the ideal ages to have babys?

In: Biology

Many animals have a specific mating season to try and time their births with the seasons rather than trying to raise young in the winter.

Humans come from a place that has little seasonal variety and are useless infants for over a year, so there’s no value in trying to time births with seasons – they can mate year round.

This is common among species that don’t deal with seasonal shifts.

For puberty and offspring volume, remember this all evolved when we lived in caves. There’s no benefit to “building a career first” when your career is “caveman”

1) humans are a species that needs a lot of work to raise children. It’s advantageous to have multiple people caring for children, so parents bonding together for a long time to raise children was a positive trait during human evolutionary history. With women able to have sex every day (rather than just a short period of time each month for estrus, such as is the case in chimpanzees) increases the bonding between a man and a woman, increasing the chances that they will stay together long term to raise their child

2) One of the closest ape relatives of humans, bonobos, also can have sex at any time, and they are very promiscuous, using sex to bond with others, to greet others in a friendly way, to resolve conflicts, or just recreationally. In many other species, males might be able to have sex at any time, but won’t be interested in sex until they get a signal from a female, such as seeing a female in heat. But females typically only express interest in sex during a narrow window of time.

3) People reach puberty now much earlier than we did during most of human history. Girls had their first menstrual period around age 16, not age 11 as today, and boys reached puberty when older, too. But because our diet and exercise regimen is very different today than in those earlier times, we are sending signals to the body to start puberty earlier, long before children are emotionally mature enough to have sex and children. Even when girls got their first period at 16, they typically were not reliably fertile and able to get pregnant for a few years, meaning that first motherhood happened closer to age 18 or 20.

Humans spontaneously ovulate as well as other primates, rats, mice, gueina pigs and sheep. Other animals have induced ovulation where sex induces ovulation.

Prior to modern times humans might not know when they are ovulating so being interested in sex all the time helps ensure that eventually the sex will line up with ovulation.

For induced animals they also tend to follow a estrous instead of a menstrual cycle. So they only need to have sex during certain times of the year and because they are induced ovulators they will produce an egg after sex. So they aren’t likely to miss reproduction. If animals have estrous cycles they don’t have periods instead they will reabsorb the lining. Sometime you might see spotting but that happens during ovulation which is the opposite of a period.

It doesn’t make sense for an 11 year old boy to have many offspring. We aren’t fruit flies. Humans do not need to procreate in mass numbers to sustain the population. Our population is dependent on nurturing, caring parents. So that theory of why men are horny doesn’t make much sense.

We cognitively developed enough to have our basic needs met to where women ovulate regularly year round. Other animals are still dependent on the environment providing their basic needs and must conserve energy and only use it when conditions are favorable.

Short answer: there were also humans who didn’t like sex, but they didn’t have any offspring. All our grandfathers are the horny ones.

What does “being in heat” mean?

Bonobos are a related primate and they spend all damn day screwing. Chimps go to war all the time. Humans are somewhere in the middle. Some love some war.

The Naked Ape by Desmond Morris tries to answer most of the OPs questions. He also postulates in the book that due to sexual selection in human evolution, humans tend to have the highest ratio of penis size to body mass in higher primates. 

Wow. What a way to put it.

I WISH everyone was always in heat lol.

We aren’t. But i understand what you are asking.

Animals go into heat. There are many reasons for this, but I can summarize them as saying, when you are part of the food chain, it’s really not a good idea to be caught “with your pants down”. That’s why animals will go into heat periodically when it is “generally safer” to be messing around. The more communal an animal is, the more likely they will be fertile at the same time, like penguins.

Humans however, are a different animal all together. First, remember that for thousands of years, life expectancy was.. like.. 30 years. Humans needed to have as many children as possible as often as possible just to survive.

Additionally, there’s sapience. As our brains grew, the need to be FORCED into sex by instinct lessened.. sex became more and more a conscious decision and not an instinctive one. With no natural predators and intelligence we could choose when to have sex.. and even better, our genitals don’t need to turn bright red!

We are not “always in heat”. We are NEVER in heat. We just don’t need it.