I'm glad you asked about human evolution! Not only is it extremely interesting to learn about, it is very important and the next federal budget should include additional funding for human evolution research.
Studying human evolution has come a long way and new things are being discovered everyday. Considering that paleoanthropologists only started believing we evolved out of Africa in the 1940's, and this was a huge debate which worked (and continues to work) to break down a lot of colonialist thought and racism, there is a lot left to do. Studying the human past helps shape the way we think about ourselves and our future and more funding would allow more scientists from all around the world to work together to create more open discussions; and ultimately, create a more accurate view of our past and present.
Human evolution research also does a lot with genetics and this research helps us to better understand our bodies and health and can help us predict how we might have evolved and how we could evolve in the future. Better understanding how evolution could affect our bodies will be of great importance to our future lives and future health.
Wednesday, June 24, 2020
Monday, June 22, 2020
Friendship at Drimolen
Hey there. They call me Paranthropus robustus. I am gonna stick to that name because my real name is pretty hard to pronounce. I have been hanging out at Drimolen for about 2 million years now and a lot has changed. I have learned a lot from listening to the paleoanthropologists around, but I can't say I agree with everything.
Don't get me wrong, I am extremely flattered to be taken so seriously and I feel very special getting my own species name (some skeletons dream of the day), but I feel kind of weird being thought of so differently than Australopithecus and Homo erectus over there. I also feel a little self conscious when they talk about my sagittal crest and my big molars. I mean, they did me justice for a long time! These insecurities are only recent, though! Back in my day (👴) we did not observe every little detail of someone and point out all the differences and similarities between us (I am sorry if this is a generalization, I don't get out much. All my social interaction is at the site). I mean sure, I knew Australopithecus and Homo erectus were a bit different. It is hard not to notice Homo erectus over there constantly doing the most, making tools, always communicating BUT we all made it work. I mean we were not the pickiest bunch and we felt more similar than we did different. No one was pointing out my sagittal crest or the brain case of Homo erectus. Communication could be hard at times, but some ended up mating. At the end of the day, we ate pretty similar things and we were all trying to survive. The climate was changing pretty rapidly and survival was on all of our minds. I honestly can't remember any time I really pointed out the features of another, but I do remember worrying about how cold it was and I know for sure I wasn't the only one.
Anyways, I don't mean to ramble, and I know many of my friends didn't survive to see the paleoanthropologists so it is hard to tell, but a lot has changed about how we see each other. A lot of interaction was not based around how we looked. There were no pictures, no Instagram, no Woman Crush Wednesday. There was also no Google Translate, although this would have made our lives much easier and I am sure much more peaceful at times, but your bones lives on and you learn, right?
Take care, see ya next time you're in the area.
Don't get me wrong, I am extremely flattered to be taken so seriously and I feel very special getting my own species name (some skeletons dream of the day), but I feel kind of weird being thought of so differently than Australopithecus and Homo erectus over there. I also feel a little self conscious when they talk about my sagittal crest and my big molars. I mean, they did me justice for a long time! These insecurities are only recent, though! Back in my day (👴) we did not observe every little detail of someone and point out all the differences and similarities between us (I am sorry if this is a generalization, I don't get out much. All my social interaction is at the site). I mean sure, I knew Australopithecus and Homo erectus were a bit different. It is hard not to notice Homo erectus over there constantly doing the most, making tools, always communicating BUT we all made it work. I mean we were not the pickiest bunch and we felt more similar than we did different. No one was pointing out my sagittal crest or the brain case of Homo erectus. Communication could be hard at times, but some ended up mating. At the end of the day, we ate pretty similar things and we were all trying to survive. The climate was changing pretty rapidly and survival was on all of our minds. I honestly can't remember any time I really pointed out the features of another, but I do remember worrying about how cold it was and I know for sure I wasn't the only one.
Anyways, I don't mean to ramble, and I know many of my friends didn't survive to see the paleoanthropologists so it is hard to tell, but a lot has changed about how we see each other. A lot of interaction was not based around how we looked. There were no pictures, no Instagram, no Woman Crush Wednesday. There was also no Google Translate, although this would have made our lives much easier and I am sure much more peaceful at times, but your bones lives on and you learn, right?
Take care, see ya next time you're in the area.
Friday, June 12, 2020
Careful Climbing in the Miocene- Lovejoy2009
https://www.youtube.com/watch?v=zyl6eoU-3Rg
First three minutes of this video are a good preview for this paper: https://app.perusall.com/courses/human-evolution-3/99d_lovejoy_et_al_2009_careful-climbing-in-the-miocene
Good information about rays and mobility:
https://www.orthonet.on.ca/core-topics/hand-and-wrist-topics/hand-anatomy-1/
Ardipithecus ramidus hand
When determining the defining features of a species and where it fits in evolutionary history, we typically think of looking at the skull, spine, teeth, jaw and probably some leg bones, but an important discovery was made studying the hand of Ardipithecus ramidus. This makes sense because some defining characteristics of primates are grasping hands and highly mobile forelimbs. Bones in other areas pointed to a common ancestor that had more climbing abilities and spent more time in the trees (suspensory locomotion, vertical climbing, knuckle-walking) than we do today. The nearly complete fossils of Ardipithecus ramidus' hand show that we are much closer to our relative than previously believed. Studies published in 2009 point to a human hand is probably more primitive than a chimpanzee hand is. This amazes me because whenever scientists are studying chimpanzees and claim that studying them will tell us about our past, it is assumed that the chimpanzees are the more primitive of the two.
There are some key differences (very condensed because I have not taken human anatomy or osteology and can barely tell phalanges from a femur) that tell us some interesting things about the potential locomotion of our ancestors:
-Human palms are shorter and our wrists are more mobile which helps us to have a "power grip" (the important grasping hands that I mentioned before)
-Ardipithecus hand fossils show that they did not knuckle walk or have the adaptations for reducing injuries that come with climbing/spending time in trees that great apes have
-"We now know that our earliest ancestors only had to slightly enlarge their thumbs and shorted their fingers to greatly improve their dexterity for tool-using" (Lovejoy et. al, 2009)
-Ardipithecus ramidus was both terrestrially bipedal and arboreally capable
-Thickening of CJC ligaments is a sign that a species engages in suspension (examples are Pongo, Pan, and Gorilla)
-The CJC of Ardipithecus suggests that "the earliest hominids and their immediate ancestors did not engage in habitual suspension or vertical climbing"
Since the "Careful Climbing in the Miocene : The Forelimbs of Ardipithecus ramidus and Humans Are Primitive" scientific paper came out in 2009, I figured that maybe some new information came out (because the goal is to keep professors and students always wondering if the iformation is still relevent, right?) so I looked into some newer articles. One I came across, "The African ape-like foot of Ardipithecus ramidus and its indications for the origin of bipedalism," which is from 2019 makes it seem like the Lovejoy et. al paper is not the whole story (ofc).
"The hand of Ar. ramidus was argued not to display traits associated with forelimb suspension in extant taxa or show evidence of a knuckle-walking ancestry (White et al., 2015; Lovejoy et al., 2009b; Almécija et al., 2015), but many of those observations have not yet been independently validated. The terrestrial specializations of the hominine foot are likely to be homologous because they are present in Ar. ramidus and they are consistent with model-based ancestral estimations. Critically, they carry a similar set of implications for the origin of bipedalism regardless of the terrestrial hand posture of the Homo-Pan LCA."
So....vertical climbing? Semi-terrestrial quadrupedalism? More chimp than the Ardipithecus ramidus hand shows?
https://elifesciences.org/articles/44433
And since I think memes are perfect I will add some more I think are funny and relevant...
First three minutes of this video are a good preview for this paper: https://app.perusall.com/courses/human-evolution-3/99d_lovejoy_et_al_2009_careful-climbing-in-the-miocene
Good information about rays and mobility:
https://www.orthonet.on.ca/core-topics/hand-and-wrist-topics/hand-anatomy-1/
Ardipithecus ramidus hand When determining the defining features of a species and where it fits in evolutionary history, we typically think of looking at the skull, spine, teeth, jaw and probably some leg bones, but an important discovery was made studying the hand of Ardipithecus ramidus. This makes sense because some defining characteristics of primates are grasping hands and highly mobile forelimbs. Bones in other areas pointed to a common ancestor that had more climbing abilities and spent more time in the trees (suspensory locomotion, vertical climbing, knuckle-walking) than we do today. The nearly complete fossils of Ardipithecus ramidus' hand show that we are much closer to our relative than previously believed. Studies published in 2009 point to a human hand is probably more primitive than a chimpanzee hand is. This amazes me because whenever scientists are studying chimpanzees and claim that studying them will tell us about our past, it is assumed that the chimpanzees are the more primitive of the two.
There are some key differences (very condensed because I have not taken human anatomy or osteology and can barely tell phalanges from a femur) that tell us some interesting things about the potential locomotion of our ancestors:
-Human palms are shorter and our wrists are more mobile which helps us to have a "power grip" (the important grasping hands that I mentioned before)
-Ardipithecus hand fossils show that they did not knuckle walk or have the adaptations for reducing injuries that come with climbing/spending time in trees that great apes have
-"We now know that our earliest ancestors only had to slightly enlarge their thumbs and shorted their fingers to greatly improve their dexterity for tool-using" (Lovejoy et. al, 2009)
-Ardipithecus ramidus was both terrestrially bipedal and arboreally capable
-Thickening of CJC ligaments is a sign that a species engages in suspension (examples are Pongo, Pan, and Gorilla)
-The CJC of Ardipithecus suggests that "the earliest hominids and their immediate ancestors did not engage in habitual suspension or vertical climbing"
Since the "Careful Climbing in the Miocene : The Forelimbs of Ardipithecus ramidus and Humans Are Primitive" scientific paper came out in 2009, I figured that maybe some new information came out (because the goal is to keep professors and students always wondering if the iformation is still relevent, right?) so I looked into some newer articles. One I came across, "The African ape-like foot of Ardipithecus ramidus and its indications for the origin of bipedalism," which is from 2019 makes it seem like the Lovejoy et. al paper is not the whole story (ofc).
"The hand of Ar. ramidus was argued not to display traits associated with forelimb suspension in extant taxa or show evidence of a knuckle-walking ancestry (White et al., 2015; Lovejoy et al., 2009b; Almécija et al., 2015), but many of those observations have not yet been independently validated. The terrestrial specializations of the hominine foot are likely to be homologous because they are present in Ar. ramidus and they are consistent with model-based ancestral estimations. Critically, they carry a similar set of implications for the origin of bipedalism regardless of the terrestrial hand posture of the Homo-Pan LCA."
So....vertical climbing? Semi-terrestrial quadrupedalism? More chimp than the Ardipithecus ramidus hand shows?
https://elifesciences.org/articles/44433
And since I think memes are perfect I will add some more I think are funny and relevant...Monday, June 8, 2020
The Secret Life of Bipedality: Foramen Magnum
One of the ways that paleoanthropologists determine whether or not a fossil could be a hominid, or whether or not they could potentially have been bipedal, is to determine the position of the foramen magnum. "The foramen magnum (from the Latin, meaning "great hole") is the large opening in the base of the skull through which the spinal chord exits the cranial vault (Beasley, n.d.). The position of the foramen magnum gives an indication of what kind of locomotion the species had. In bipedal organisms the position of the foramen magnum is central under the braincase. In other species, like chimpanzees and most other mammals, the foramen magnum is toward the back of the skull. This is due to the spine being positioned more behind the head.
https://carta.anthropogeny.org/moca/topics/foramen-magnum-placement
https://www.sciencedaily.com/releases/2013/09/130926111903.htm
https://www.lahc.edu/library/documents/parikh/Bio%20Anthro-Skeletal%20Features%20of%20Bipedalism.pdf
https://carta.anthropogeny.org/moca/topics/foramen-magnum-placement
https://www.sciencedaily.com/releases/2013/09/130926111903.htm
https://www.lahc.edu/library/documents/parikh/Bio%20Anthro-Skeletal%20Features%20of%20Bipedalism.pdf
Friday, June 5, 2020
Why Are There Still Chimps?
One of my anthropology professors said that during one of his lessons about evolution a student commented "I didn't come from no monkey." He said his response was "You are right. You did not. But you do have a common ancestor."
I also had a similar encounter with another student who said they were "not sure if they believed in evolution because they don't believe we came from monkeys."
Evolution can be very confusing and a lot of people (including myself for quite some time) think of evolution as being linear. This species gave rise to only that species and so forth. That is what the evolution bumper stickers make it look like. They also make it look like we came from chimpanzees, which is even more confusing considering chimpanzees are still around. So why, then are chimpanzees still around? What even is a common ancestor?
It is a common known fact that we share 98% of our DNA with chimpanzees. We are certainly related to them, but not in the way we tend to think of. We actually have a common ancestor with chimpanzees that is known as Sahelanthropus tchadensis. This species was discovered in Chad and lived around 6-7 million years ago and gave rise to other species in our evolutionary history, including chimpanzees and humans. It was not a linear history that brought us to where we are today. One species gives rise to another and they can split, like branches.
It is also weird to think that we are so different from chimpanzees even though we share so much DNA. It made me curious as to how genetically we can be so similar and yet be so different. In one article it discusses how the same genes can be turned on and off to ultimately provide different functions. "...even two identical stretches of DNA can work differently --they can be 'turned on' in different amounts, in different places or at different times" (DNA: Comparing Humans and Chimps, n.d.). A major example of this is the genes in the brain. Thousands of differences can greatly affect brain development and function.
Hominid Evolution
Skull of Sahelanthropus tchadensis
Chimpanzee Skull
Human Skull
https://www.amnh.org/exhibitions/permanent/human-origins/understanding-our-past/dna-comparing-humans-and-chimps
https://www.abc.net.au/science/articles/2011/10/04/3331957.htm
Saturday, May 30, 2020
Lessons From Non-Human Primates
When I was in elementary school I became very interested in chimpanzees. I (like many other people) fell in love with how human-like they seemed, and I could easily believe that we could learn so much from studying them. Watching many documentaries about chimpanzees and seeing the work done by Jane Goodall, it was fascinating learning all of the amazing things chimpanzees do and are capable of. It is easy to see ourselves in other non-primates and even easier when we know how closely related we are to chimpanzees; but, as time has passed, what I believe chimpanzees and other non-human primates can teach us about "being human" has changed.
Chimpanzees are not humans. They are intelligent, social, strong, and curious creatures, but they are not humans. Believing that studying chimpanzees can teach us about the behavior of our human past is not right. Chimpanzees and humans are different species with different evolutionary pasts and although chimpanzees are amazing and it would be great to have a living link with which to understand our past, I think it does both of us a disservice. Learning about chimpanzees is fascinating and they are very important ecologically and we can thank them for some big advances in biomedicine (which we should since animal testing is extremely traumatic for chimpanzees), but looking to non-human primates for information about our evolutionary past has proved problematic before.
The biologist St. George Jackson Mivart, believed (in 1889) that Asia gave rise to our ancestors and he believed that gibbons were key to understanding our past because they were so similar to us. "He, therefore, gave great weight to traits such as the human-like liver of gibbons (vs. the “brutal” liver of gorillas), the apparent chin and “aquiline nose” of the siamang and Hoolock gibbon, their propensity to walk bipedally when on the ground and, most notably, their monogamy. The seemingly civilized gibbons were thus a more appealing ancestor to (Western European male) humans" (Athreya & Ackermann, 2018). Reading this was extremely concerning to me because a) what on earth is a "brutal" liver? b) monogamy is not seen in all human societies c) gibbons RARELY come to the ground and d) our ancestry does not have to be appealing.
Using non-human primates to "understand" our human past can be confusing and I think it is easy for people to justify their connections to animals in their research with "facts." I think it can be easy for scientists to "discover" things that are not there because they are more "appealing to humans," and they make it easier to get published and get grant money for future research.
Another example of why it can be problematic to study chimpanzees for the purpose of understanding humans is that it has been said that we as humans are naturally violent, and one could justify this with the evidence of warfare and cannibalism in chimpanzee troops. This is a controversial topic, though. Are we inherently violent? Also, if bonobos are also very closely related to us then why are they not known to be inherently violent?
As anthropologists, biologists, psychologists, sociologists, etc. it is our duty to think critically about our studies. It is crucial that we do not let our upbringings, our pasts, our desired outcomes for research, our connections to animals alter the quality of our work and keep us from challenging popular beliefs. We also need to be aware of the effect of our research on society and conservation.
Chimpanzees are not humans. They are intelligent, social, strong, and curious creatures, but they are not humans. Believing that studying chimpanzees can teach us about the behavior of our human past is not right. Chimpanzees and humans are different species with different evolutionary pasts and although chimpanzees are amazing and it would be great to have a living link with which to understand our past, I think it does both of us a disservice. Learning about chimpanzees is fascinating and they are very important ecologically and we can thank them for some big advances in biomedicine (which we should since animal testing is extremely traumatic for chimpanzees), but looking to non-human primates for information about our evolutionary past has proved problematic before.
The biologist St. George Jackson Mivart, believed (in 1889) that Asia gave rise to our ancestors and he believed that gibbons were key to understanding our past because they were so similar to us. "He, therefore, gave great weight to traits such as the human-like liver of gibbons (vs. the “brutal” liver of gorillas), the apparent chin and “aquiline nose” of the siamang and Hoolock gibbon, their propensity to walk bipedally when on the ground and, most notably, their monogamy. The seemingly civilized gibbons were thus a more appealing ancestor to (Western European male) humans" (Athreya & Ackermann, 2018). Reading this was extremely concerning to me because a) what on earth is a "brutal" liver? b) monogamy is not seen in all human societies c) gibbons RARELY come to the ground and d) our ancestry does not have to be appealing.
Using non-human primates to "understand" our human past can be confusing and I think it is easy for people to justify their connections to animals in their research with "facts." I think it can be easy for scientists to "discover" things that are not there because they are more "appealing to humans," and they make it easier to get published and get grant money for future research.
Another example of why it can be problematic to study chimpanzees for the purpose of understanding humans is that it has been said that we as humans are naturally violent, and one could justify this with the evidence of warfare and cannibalism in chimpanzee troops. This is a controversial topic, though. Are we inherently violent? Also, if bonobos are also very closely related to us then why are they not known to be inherently violent?
As anthropologists, biologists, psychologists, sociologists, etc. it is our duty to think critically about our studies. It is crucial that we do not let our upbringings, our pasts, our desired outcomes for research, our connections to animals alter the quality of our work and keep us from challenging popular beliefs. We also need to be aware of the effect of our research on society and conservation.
Extra interesting articles (sources):
Monday, May 25, 2020
Hello There!
Hey guys!
My name is Stephanie and I am a senior at App State (🎉). I am majoring in Biological Anthropology and minoring in Biology and Spanish. I am excited about this class and look forward to learning from you all and having some great discussions! I hope everyone is doing well and your summers are off to a wonderful start!
My name is Stephanie and I am a senior at App State (🎉). I am majoring in Biological Anthropology and minoring in Biology and Spanish. I am excited about this class and look forward to learning from you all and having some great discussions! I hope everyone is doing well and your summers are off to a wonderful start!
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