Love is in the air….

gorillas huggingAs we study reproduction and development during this Valentine’s Day week, Time Magazine has an article about an unusual mating behavior observed in a group of lowland gorillas that live in a national park in the Congo. Normal gorilla mating behavior involves the mating pair meeting and mating face-to-back. The gorilla pair described in the article, George and Leah, mate while facing one another, which is highly unusual and in fact, is quite rare in the animal kingdom, at least among mammals. Many bird species are monogamous, only mating with one partner–some for a mating season, some for life.

Gorillas, like many other animals, are not monogamous–in fact, they are known for their polygamy. But face-to-face mating could indicate a move toward monogamous behavior, at least for this particular mating pair. From an evolutionary biology perspective, a polygamous organism switching gears to monogamy could have important implications for the gorilla gene pool. Think about the advantages of polygamy versus monogamy in terms of increasing an individual’s genes in the gene pool. What would become of them if, over time, gorillas became monogamous instead of polygamous? Might this endanger gorillas as a species?

46 thoughts on “Love is in the air….

  1. Hannah Dunn

    Having monogamous relationships could be a danger for gorrilas in the fact that they would produce less offspring however their gene pool would be more diverse because there would only be a select number of gorillas being born by the same father. That would also mean a complete change in the way a gorilla’s society is run because usually it is one male to several females. Most likely the male would be centered around its mate and then their offspring until they were ready to go off on their own.

  2. Hannah Dunn

    I think the most interesting thing about this is maybe gorillas are evolving. Maybe the frontal lobe of the brain in these gorillas has evolved to include a more exclusive view on a mate more like us humans. Possibly this is how humans evolved as well starting with thinking only with the behavioral part of the brain, the brainstem, and moving more towards using the frontal lobe as its capacity for emotions and thought grew.

  3. Andrea Deschenes

    With polygamy the gorilla gene pool would be much more diverse and much larger. With monogamy the number of gorillas mating would be limited and the diversity in genes would be reduced. With one mate there is only a very limited amount of offspring that can be reproduced verses many offspring. Also if the monogamous gorilla realizes that its mate cannont reproduce fertile offspring than that male gorilla has pretty much no chance at spreading his genes. So overall I think that in the animal kingdom it is necissary to have many mates in order to keep a population flourishing and diverse.

  4. David Golynskiy

    This behavior is probably because of some evolutionary phenomenon. But, it should not take over the gorilla population. If this is truly unfavorable, then based on evolutionary concepts, it should not continue to happen in gorillas. Their polygamy is a major advantage for survival and progression of the species.

    As a side note, it would be interesting to see the scientist observe the male gorilla and female gorilla to see how they interact with other gorillas and whether they mate differently with different gorillas.

  5. Jocelyne

    Its cute, but in the long run this could have a bad effect on the gorilla population. Having multiple partners enables gorillas, as well as other species, to pass more of their DNA on and produce more offspring. keeping with one mate for the rest of their lives could be fatal for the population if that male or female posses undesirable traits.

  6. Jocelyne

    I agree that the monogamous aspect of the ritual might be alarming for the population but overall I would hardly call this discovery a possible, “sexual revolution” for the gorilla species. There needs to be more observation taken place in a longer time span.

  7. ethan nelson

    the move to the monogamous behavior in the gorillas could indeed be detremental the species. it could very well endanger their way of life. however we for the most part we are monogamous and have we suffered becuase of it? it is interesting note that we are a very sucessful species and we are monogamous.

  8. Angie

    The practice of polygamy certainly allows individuals to pass on more of their genetic material. A shift towards monogamy might hinder the gorilla species because one pair would only produce one baby in a gestation period which in this species is about 250 days. This would decrease populations of a species with already low populations. Also, isn’t the dominant male the only one that is allowed to mate with the females? This would change up the hierarchy in gorilla society.

  9. Angie

    I remember watching the Bonobo video in tthe first semester and it talked about how Bonoboes are unusual in that they sometimes mate face to face (among other behaviors) but Bonoboes certainly aren’t monogamous.

  10. Pingback: incorporated subversion - education, media, community » Blog Archive » CommentPress in action on Edublogs

  11. scienceguru Post author

    You’re right, in gorilla society, the silverback males are the ones typically allowed to mate. If they suddenly became monogamous, think about the bottlenecking that would take place!

  12. scienceguru Post author

    Alas, that is the disadvantage to monogamy…if you or your mate have a few bad genes and you keep passing them on…it does little good for the fitness of your offspring!

  13. Andrea Deschenes

    It would be cute if the Gorillas became monogamous and had little gorilla weddings but under their society standards and conditions it would kill off their species. If one male could mate, and had one mate, they would produce minimal offspring. Also what if the female the one male mated with had a gene that could be harmful to the offspring if passed down. The male gorilla would jeopardize his successful reproduction and passing of his genes. So basically humans should be monogamous while gorillas should stay polygamous 🙂

  14. Ty Vessels

    This story reminds me of the bonobos too. This face to face mating is quite a discovery for the polygamous gorillas. However since this mating style pertains to only one couple of gorillas I wouldn’t quite say that the whole population of gorillas is in danger due to a switch in sexual practice. More research needs to be done and more gorillas need to be observed before this can become a serious issue.

  15. Kelsey Wise

    I was just wondering if this is really a rare phenomenon or if we just happened to notice this behavior in an isolated group, because gorillas are known to be pretty intelligent and possess some characteristics vaguely similar to those of humans. However, if this is truly evolutionary, I do think this would endanger the gorillas species because it is their polygamy that keep this overall endangered species alive. If their reproduction was confined, the species might eventually dwindle away

  16. Kaston Murrell

    I agree with Golynskiy, it could be an evolutionary phenomenon. I also agree with the notion that it doesn’t endanger the gorilla species. If a small group goes monogamous, they will most likely be outmated by the polygamous, dominant group. Also, if it seriously limits diversity then the monogamous group would be the only one in serious danger IF there is a disaster that results in the drastic change of their habitats.

  17. Aadil Sarfani

    I think monogamy might actually be beneficial for gorillas. They take care of their offspring and live together, and also don’t move too much (as opposed to say flies). They would have a mating partner and wouldn’t have to worry about finding mates. Perhaps this monogamous behavior can have something to do with the fact that gorillas are closely related to us.

  18. Bonnie

    If the gorilla society became strictly monogamous, it would most likely have numerous effects on their population. Firstly, the female gorilla would have to be much stricter in choosing her mate, because instead of having a large opportunity to spread her genes and become “successful”, she has essentially laid all her eggs in one basket. Pun intended. Also, if gorillas were to try to maintain the size of their society, they would have to have several children together, which could cause problems if one of the partners was sterile or had an inheritable disease. This would take much longer than the gorilla’s method of polygamy- the dominant male bouncing from female to female, generating a much greater output of gorilla babies. Yet, humans have braved these disadvantages, and we seem to be doing fairly well. Perhaps this is just the evolution of gorillas taking place before our eyes. If they can learn to manipulate simple tasks such as testing water depth with a stick, they could probably learn how to manage monogamy.

  19. Jocelynn

    Gorillas are very much like humans as demonstrated with the observation of two gorillas “making love.” They perform sexual intercourse face to face rather than front to back followed by cuddling together. The female, Leah, was also seen putting a stick in a pond to test the depth and get the idea whether or not it is safe for her to cross. These gorillas’ intelligence amazes me.

  20. Sara Lacock

    If these gorillas are around or observe people often, they may notice that we face each other to communicate. They could have picked this up from that or else it may truly be the start of a change from monogamy to polygamy. When mates one person only their offspring will all have the chance to inheret their parents traits. If one of the gorillas has a disorder or something wrong, it could be passed down to offspring moreso than if each gorilla mated with another. Yet if both parents are well adapted to their environment, they may pass that on to their offspring. There just wouldn’t be as many genetic combinations as in a polygamous population.

  21. Kelsey Wise

    Another thought on a monogamous relationship within the gorilla population–though it would have serious impact on the gorilla population (drastic decline), wouldn’t that make natural selection speed up, because if a gorilla only chose ONE mate, they’d probably want the most *fit* gorilla, right? So if that were the case, I would think that some gorilla traits would eventually decrease, if not wear out all together.

  22. sussana elkassih

    If gorillas became monogamous instead of polygamous over time, then the gorillas (I would think) would actually help their endangered species. I remember watching that documentary in biology about the Bonobos (spelling?) and how the chimpanzees were mimicking the rough and brutal behavior of the gorillas, thus I immediately thought that gorillas were a very competitive species (that is between the males). Thus, if the individual male and female gorillas would mate with each other specifically and have offspring wouldn’t the survival rate of the offspring increase since both mother and father were watching over the child? The gene pool would also become more diverse. Not, to mention the decrease in male to male competition for holding the leader position.

  23. sussana elkassih

    It’s amazing the way that the gorillas have started evolving from polygamous organisms to monogamous organisms. I wonder if there may be anything influencing the gorillas to change their mating behavior such as: eating behavior, decrease in number of members, a major change in male/female ratio, or location of habitat. From what I just listed I would think that the change in male/female ratio would be the greatest influence on the mating behaviors of the gorillas, in which there could be so many males that competition becomes increasingly important, but on the other hand less important as each male receives a female instead of one male to various females (and vice versa).

  24. Kaitlin

    A polygamous relationship among individuals of a poplutation would obviously produce more genetic diversity. However, are there any substantial reasons for a population to maintain monogamous relationships that outweigh genetic diversity? Possibly less confrontation and better parental involvement.

  25. Brigham

    This topic insighted interesting thoughts to me. One would be, where did they learn this behavior from? Why have they decided to suddenly begin this behavior and what is adventageous about this behavior?
    I don’t really know the answer to what is advantageous about mating face to face other than the fact that it could possibly show that they are making a shift toward monogamy and away from polygamy. To the first question I speculate that they could have learned it from possibly, us humans. I don’t know if it’s a reasonable hypothesis but it makes sense to me.

  26. Sara Lacock

    That reminds me of a National Geographic article I read about the intelligence of many different animals. I think it is amazing how much comprehension animals have of the world, something that we don’t always realize because they don’t speak english. But in this article, a Bonobo named Kanzi can use more than 360 keyboard symbols and understands many spoken words. He can form sentences, follow instructions, use stone tools, and play the piano. Another one of the animals was a parrot named Alex. He could count, knew colors, shapes, and sizes and could form his wants/needs into small sentences after being taught English for many years.

  27. The Ger Bear

    Not necessarily. The father’s genes aren’t always dominant, and mixing with multiple females would create a very diverse amount of offspring. This also means that every gorilla is likely to have children of some kind, regardless if it’s with one female or more.

    I don’t think that the gorilla population would be in danger. Just look at us. The majority of us have children with a spouse, not just a sexual partner.

  28. The Ger Bear

    Ding ding ding. That’s really interesting concerning the acceleration of natural selection, and it seems plausible.

    But then again, I’m sure males would have the “something is better than nothing” mindset, and would want to have children, regardless of with whom. I don’t think the gorilla population would be in any danger.

  29. The Ger Bear

    I doubt that the gorillas would have just one child. Again, you have to look at how many gorillas there are alive right now. I have no idea about it, but I doubt they are in danger.

    I do wonder though, do the gorillas consciously acknowledge that they have to pass their genes on? I wonder if that is involved with their sexual instinct. I don’t think the idea of their traits being passed on are on their minds in the whole process.

  30. David Golynskiy

    Just to add to the “animals are amazing” theme, I had a dog when I was little, that learned to sing, kinda. When I was about 6 years old I was addicted to a song and listened to it constantly. I remember I would crank up the stereo to the max sometimes. My dog, Guy, seemed as if he like the music, he didn’t seem irritated by it like other songs. So one day I was walking with Guy and I started singing and humming the song. Suddenly, Guy bursts into a loud howling/growling/weeping going along with the tune as I sang it. I was shocked! It was bizzare because he actually made low and high pitched sounds almost exactly as in the song. Amazing right?

  31. Joshua Geevarghese

    being monogamous could lead to endanger of gorillas. when they are polygamous their genes will spread and there will be lots and lots of babies being born. but that wouldnt happen when it is monogamist

  32. scienceguru Post author

    I’d be willing to bet it’s an isolated incident. I think more behavioral studies would need to be done in order to tell if this was just a flukey occurrence, or if it was becoming a widespread behavior.

  33. scienceguru Post author

    Monogamous behavior would definitely benefit the offspring and the partners involved, as each partner would have a guaranteed mate. Offspring would have parental care from both parents, not just one.

    The question is, which sex would dominate a monogamous gorilla society? Or would gorilla society be more egalitarian in nature?

  34. scienceguru Post author

    Much better parental involvement would be an added benefit. I would imagine that less confrontation would also be a benefit but I think it would depend largely on which sex was dominant, if a single sex was to be dominant.

  35. Isha Banerjea

    Polygamy, although it should only be practiced by other species NOT including humans, is greatly beneficial to the gene pool creating an extremely diverse population. The amount of members in the population would decrease significantly if they changed their mating behaviors to monogamy, which would limit them to one partner per season or per lifetime. Instead of having numerous offspring from numerous partners, the couple would only have each other. It would be a detriment to see these gorillas to change their behavior, however, I’m not sure face-to-face mating is the beginning of such change.

  36. Kishan

    This is a very intersting article, I’ve never even thought of gorillas being monogamous. But looking at this article maybe there is a chance that gorillas are becoming monogamous. This could also mean that gorillas are evolving. But until more and more gorillas start mating while facing each other I don’t think that the gorilla race is truly evolvin, this could just be a one time thing. But at least there is hope that we are seeing some kind of evolution occur before our eyes.

  37. Kristal Jackson

    I think that becoming monogamous would endanger the species. By mating with only one other partner, the pair could risk passing on faulty genes and other undesirable traits. The reason that animals aren’t monogamous is to increase the genetic diversity.

  38. Marcos

    Devil’s advocate for the Gorillas says that we humans are reading too much into this. He says that the Gorillas just want to get lost in each other’s eyes. Is that too much to ask? George and Leah feel discriminated against as the instigators of social and evolutionary change in their species. They do not appreciate being called out.

  39. Marcos

    Now that up there was the Devil’s advocate, you always have to take him with a grain of salt. ahem. I myself was originally thinking that this couple was a radical minority. But then I read the article and it noted that George was the dominant male, so he has to be somewhat orthodox at least to arrive at the station of dominant male. So what we can say is that George has converted to reformer, or that Leah is special, or that George is ill, or that it was a clever ploy conceived to trick the humans into a false sense of security. We may never know. Just like we may never know who gassed 4th period today. hmm.

  40. Kamene Dornubari-Ogidi

    I completely agree. I know there are man Jane Goodalls of the gorilla orientation that observe them unceasingly, but really!

    In order for this deviant ( or what they propose is deviant) behavior to be occuring, there must be a start. Are there a particular group of gorillas that mate that way, and is face-to-face the only way they mate?

  41. Kamene Dornubari-Ogidi

    I don’t completely agree with the statement that face-to-face mating might be heralding a new era of monogamous gorilla populations.

    I’m not very knowledgeable about animals and the thinking that goes on in the brain. However, I don’t think that, like humans, they experience more intimacy from face-to-face mating that would cause them to stick with one gorilla. And if they did…it would be very…strange to say the least. Male gorillas are very oppressive towards their female counterparts and aggressive towards offspring. With this in consideration, it is highly unlikely that monogamy stemming from companionship between two gorillas would occur.

  42. Kamene Dornubari-Ogidi

    I do think that if there is a shift from polygamy to monogamy in a vast population of gorilla populations, then the species, over time, might become endangered. Gorillas don’t have many offspring at a time, or that often. So polygamy aids in their population growth. However, dedication to one partner would completely change that.

    And in part I agree with Hannah Dunn’s comment, that the gorillas might be evolving. I wouldn’t necessarily say they are begining to aquire human characteristics, because they already have, but I would say they’re changing. And maybe…there might be…something in the genes of these gorillas that may be passed on to offspring. In which case the “transformation” from polygamy to monogamy would begin. And truth be told…even if there weren’t some deviation in their genes that caused this behavior, if the two gorillas that were seen mating stay togeter AFTER the child’s birth…then the child will most likely mimic their mating methods.

  43. Prashi

    Gorrilas have been tamed to talk to us using sign language, they are very smart animals, maybe watching each other during sex gave them a different bonding and they felt better with just each other.

  44. Prerak Patel

    I do not believe that if, over time, gorillas become monogamous, it would not adversely affect the species. Parents would take greater care of their children meaning that they would survive longer. This offsets the population loss caused by keeping only a single mate. If a genetic disease entered the gene pool, monogamous gorillas would spread the disease to the extent that a polygamous gorilla would.

Comments are closed.