from the world's big
Some fish evolved legs and walked onto the land. Right?
Evolution explains how all living beings, including us, came to be. It would be easy to assume evolution works by continuously adding features to organisms, constantly increasing their complexity.
An orangutan has settled into a Florida home after a court granted her personhood rights. But what is the basis for personhood?
- An orangutan named Sandra was granted non-human personhood rights in 2015 and has been moved from the Buenos Aires Zoo to a home in Florida.
- Legal personhood is not synonymous with human being. A "non-human person" refers to an entity that possesses some rights for limited legal purposes.
- Sentience might be the characteristic necessary for granting legal rights to non-human species.
Non-human person definition<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="34b8dc86facdf829e69fc81c3e42d4f0"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/proXzAtbRzI?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span><p>According to <a href="https://www.law.cornell.edu/wex/legal_person" target="_blank">legal terminology</a>, legal personhood is not exactly synonymous with human being. The law divides the world between two entities: things and persons. <a href="https://www.forbes.com/sites/andreamorris/2018/03/13/can-you-be-a-person-if-youre-not-human/#c1b2c212f7f1" target="_blank">According</a> to the Nonhuman Rights Project executive director, attorney Kevin Schneider, personhood is best understood as a container for rights. Things have no rights, but once an entity is defined as a person it can obtain some rights. So, a "non-human person" refers to an entity that is guaranteed some rights for limited legal purposes.</p><p>In Sandra's case, the ruling undercut species-membership as the basis for legally denying rights, freedoms, and protections. The Association of Officials and Lawyers for Animal Rights <a href="https://www.reuters.com/article/us-argentina-orangutan/captive-orangutan-has-human-right-to-freedom-argentine-court-rules-idUSKBN0JZ0Q620141221" target="_blank">based its argument</a> that Sandra should not be treated as an object based on the orangutan's "sufficient cognitive functions." But <a href="https://animalstudiesrepository.org/cgi/viewcontent.cgi?article=1394&context=animsent" target="_blank">others have argued</a> that it is sentience, rather than cognitive complexity, that is the essential characteristic for granting legal rights to non-human species.</p><p>The judge in Sandra's case agreed, telling the Associated Press that by giving Sandra non-human person status she wanted to shift society's view on other-than-human beings by telling them that "animals are sentient beings and that the first right they have is our obligation to respect them." </p>
Degrees of Sentience<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMjA4MTg0MC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYxMzI1MzkyM30.9rE_CDx9IeZdF7ckvbrCAu8X6HJb8QrPlYzI7BK3BBA/img.jpg?width=1245&coordinates=0%2C258%2C0%2C259&height=700" id="f672e" class="rm-shortcode" data-rm-shortcode-id="9092960947796b49e2e5b9f4bc4aea40" data-rm-shortcode-name="rebelmouse-image" />
Photo Source: Wikimedia<p>Sentience is defined as the ability to perceive one's environment and translate those perceptions into various feelings, such as suffering or pleasure. This has little to do with a species' cognitive ability. </p><p>It's been argued that it is <a href="https://www.reuters.com/article/us-argentina-orangutan/captive-orangutan-has-human-right-to-freedom-argentine-court-rules-idUSKBN0JZ0Q620141221" target="_blank">inappropriate to humanize</a> animal behavior in this way. Yet, science can never be totally free from this anthropomorphism, and there's a solid argument as to why.</p><p>For one, humans can only ever think about animals by drawing on their own experiences, and this facilitates many of the research questions when studying other species. Yet, beyond scientific discovery, there is an ethical motivation for relating human emotions to animal experiences. Once we accept that other species might feel pain similar to what we feel, we become responsible for their suffering. </p><p>Anthropomorphism, when used responsibly, can add emotional meaning to the science of animal sentience. </p><p>But is there a distinction to be made between sentient species? After all, we are animals. Yet, humans differentiate ourselves from other types of animals. Our culture, and the taxonomies our fields of study rely on, demand categorizations of nature. But nature is not so obedient. </p><p>Research indicates that sentience extends to a wide range of animals. For example, chimps have been found to be <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3158226/" target="_blank">generous</a>, mice have <a href="https://www.ncbi.nlm.nih.gov/pubmed/16809545" target="_blank">exhibited empathy</a> and honeybees have <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3158593/" target="_blank">demonstrated pessimism</a>. But because of the limits of human perception, we don't have sufficient ways to measure just <em>how</em> sentient non-human species are. It likely isn't a clear-cut answer of sentient or not sentient, but <a href="https://animalstudiesrepository.org/cgi/viewcontent.cgi?article=1343&context=animsent" target="_blank">shades of grey</a>. </p><p>Currently, most of the research on animal sentience has focused on vertebrate species and been mammal-centric. It is generally accepted that vertebrates (with the disputable exception of fish) are sentient, and that <a href="https://www.tandfonline.com/doi/abs/10.1207/S15327604JAWS0402_9" target="_blank">invertebrates are less-so</a>. These evolving distinctions have made nonhuman personhood protections a messy legal area. </p><p>Admittedly, humans have something these other sentient beings apparently do not: The cognitive ability to create complex cultures which have allowed us to conceive of and communicate a claim of rights. But, as environmental researcher Uta <a href="https://animalstudiesrepository.org/animsent/vol3/iss23/2/" target="_blank">Maria Juergens has argued</a>, "If we pride ourselves on our unique intellect, we ought to also pride ourselves on assuming the responsibility that comes with it."</p>
Experts argue the jaws of an ancient European ape reveal a key human ancestor.
- The jaw bones of an 8-million-year-old ape were discovered at Nikiti, Greece, in the '90s.
- Researchers speculate it could be a previously unknown species and one of humanity's earliest evolutionary ancestors.
- These fossils may change how we view the evolution of our species.
Rethinking humanity's origin story<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8xOTQwNzQyMC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYwNDYyMDY0Nn0.aHF-2w0zRWpAulb1zE_RDn3gXcAvODm_5lyQwt2ycvY/img.jpg?width=1245&coordinates=0%2C17%2C0%2C22&height=700" id="fbc85" class="rm-shortcode" data-rm-shortcode-id="70d8bb829b135530ca5dec10a7a02b95" data-rm-shortcode-name="rebelmouse-image" />
The frontispiece of Thomas Huxley's Evidence as to Man's Place in Nature (1863) sketched by natural history artist Benjamin Waterhouse Hawkins. (Photo: Wikimedia Commons)<p>As reported in <a href="https://www.newscientist.com/article/mg24232263-300-did-the-ancestor-of-all-humans-evolve-in-europe-not-africa/" target="_blank"><em>New Scientist</em></a>, the 8- to 9-million-year-old hominin jaw bones were found at Nikiti, northern Greece, in the '90s. Scientists originally pegged the chompers as belonging to a member of <em>Ouranopithecus</em>, an genus of extinct Eurasian ape.</p><p>David Begun, an anthropologist at the University of Toronto, and his team recently reexamined the jaw bones. They argue that the original identification was incorrect. Based on the fossil's hominin-like canines and premolar roots, they identify that the ape belongs to a previously unknown proto-hominin.</p><p>The researchers hypothesize that these proto-hominins were the evolutionary ancestors of another European great ape <em>Graecopithecus</em>, which the same team tentatively <a href="https://www.newscientist.com/article/2132026-our-common-ancestor-with-chimps-may-be-from-europe-not-africa/" target="_blank">identified as an early hominin in 2017</a>. <em>Graecopithecus</em> lived in south-east Europe 7.2 million years ago. If the premise is correct, these hominins would have migrated to Africa 7 million years ago, after undergoing much of their evolutionary development in Europe.</p><p>Begun points out that south-east Europe was once occupied by the ancestors of animals like the giraffe and rhino, too. "It's widely agreed that this was the found fauna of most of what we see in Africa today," he told <em>New Scientists</em>. "If the antelopes and giraffes could get into Africa 7 million years ago, why not the apes?"</p><p>He recently outlined this idea at a conference of the American Association of Physical Anthropologists.</p><p>It's worth noting that Begun has made similar hypotheses before. Writing for the <em>Journal of Human Evolution </em>in 2002, Begun and Elmar Heizmann of the Natural history Museum of Stuttgart discussed a great ape fossil found in Germany that they argued could be the ancestor (broadly speaking) of all living great apes and humans. </p><p style="margin-left: 20px;">"Found in Germany 20 years ago, this specimen is about 16.5 million years old, some 1.5 million years older than similar species from East Africa," <a href="https://www.sciencedaily.com/releases/2002/02/020219075535.htm" target="_blank">Begun said in a statement then</a>. "It suggests that the great ape and human lineage first appeared in Eurasia and not Africa."</p>
Migrating out of Africa<div class="rm-shortcode" data-media_id="oZzgXq4d" data-player_id="FvQKszTI" data-rm-shortcode-id="0007d6c597f8cc6c95d9d3b5fae7c1ad"> <div id="botr_oZzgXq4d_FvQKszTI_div" class="jwplayer-media" data-jwplayer-video-src="https://content.jwplatform.com/players/oZzgXq4d-FvQKszTI.js"> <img src="https://cdn.jwplayer.com/thumbs/oZzgXq4d-1920.jpg" class="jwplayer-media-preview" /> </div> <script src="https://content.jwplatform.com/players/oZzgXq4d-FvQKszTI.js"></script> </div> <p>In the <em><a href="https://en.wikipedia.org/wiki/The_Descent_of_Man,_and_Selection_in_Relation_to_Sex" target="_blank">Descent of Man</a></em>, Charles Darwin proposed that hominins descended out of Africa. Considering the relatively few fossils available at the time, it is a testament to Darwin's astuteness that his hypothesis remains the leading theory.</p><p>Since Darwin's time, we have unearthed many more fossils and discovered new evidence in genetics. As such, our African-origin story has undergone many updates and revisions since 1871. Today, it has splintered into two theories: the "out of Africa" theory and the "multi-regional" theory.</p><p>The out of Africa theory suggests that the cradle of all humanity was Africa. <em>Homo sapiens</em> evolved exclusively and recently on that continent. At some point in prehistory, our ancestors migrated from Africa to Eurasia and replaced other subspecies of the genus <em>Homo</em>, such as Neanderthals. This is the <a href="https://news.nationalgeographic.com/news/2007/07/modern-humans-came-out-of-africa-definitive-study-says/" target="_blank">dominant theory among scientists</a>, and current evidence seems to support it best — though, say that in some circles and be prepared for a late-night debate that goes well past last call.</p><p>The multi-regional theory suggests that humans evolved in parallel across various regions. According to this model, the hominins <em>Homo erectus</em> left Africa to settle across Eurasia and (maybe) Australia. These disparate populations eventually evolved into modern humans thanks to a helping dollop of gene flow.</p><p>Of course, there are the broad strokes of very nuanced models, and we're leaving a lot of discussion out. There is, for example, a debate as to whether African <em>Homo erectus</em> fossils should be considered alongside Asian ones or should be labeled as a different subspecies, <a href="https://australianmuseum.net.au/learn/science/human-evolution/homo-erectus/" target="_blank"><em>Homo ergaster</em></a>. </p><p>Proponents of the out-of-Africa model aren't sure whether non-African humans descended from a <a href="https://www.sciencedaily.com/releases/2016/09/160921131354.htm" target="_blank">single migration out of Africa</a> or <a href="https://www.sciencedaily.com/releases/2002/03/020307074956.htm" target="_blank">at least two major waves of migration</a> followed by a lot of interbreeding. </p>
Did we head east or south of Eden?<p>Not all anthropologists agree with Begun and his team's conclusions. As noted by <em>New Scientist</em>, it is possible that the Nikiti ape is not related to hominins at all. It may have evolved similar features independently, developing teeth to eat similar foods or chew in a similar manner as early hominins.</p><p>Ultimately, Nikiti ape alone doesn't offer enough evidence to upend the out of Africa model, which is supported by a more robust fossil record and <a href="https://www.sciencedaily.com/releases/2007/05/070509161829.htm" target="_blank">DNA evidence</a>. But additional evidence may be uncovered to lend further credence to Begun's hypothesis or lead us to yet unconsidered ideas about humanity's evolution.</p>
A long-ridiculed theory about humankind's early leap of consciousness is revived.
- Terence McKenna first proposed psychedelic mushrooms as the trigger for our rapid cognitive evolution.
- McKenna's theory was called the "Stoned Ape Hypothesis."
- The hypothesis is being revisited as a possible answer to a vexxing evolutionary riddle.
The stoned ape<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8xOTM4ODA3OC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY1NTE1OTA0OX0.ceqhaKIXbvL5rY4v9tAAPSrRIoEEzDjq9q18iAD8Gzc/img.jpg?width=980" id="dc02b" class="rm-shortcode" data-rm-shortcode-id="d144cb6b63094f83f00121d425f6aac5" data-rm-shortcode-name="rebelmouse-image" />
Terence McKenna. Image source: Jon Hanna/Wikimedia<p>In McKenna's Stoned Ape hypothesis," he posited that as humans began to migrate to new areas, at some point they came upon psychedelic mushrooms growing in cow droppings, as is their wont, and then ate them. After ingesting them, and more specifically the psilocybin they contained, their brains kicked into overdrive, acquiring new information-processing capabilities, and a mind-blowing expansion of our imaginations in the bargain. Many modern users of psychedelics claim the world never looks the same again after such an experience. As McKenna put it, "<em>Homo sapiens</em> ate our way to a higher consciousness," and, "It was at this time that religious ritual, calendar making, and natural magic came into their own."</p>
The return of the stoned ape<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8xOTM4ODA0NS9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTU5OTk3MDg1N30.mWK9XCIhlVgoL8-F3hik3jqS4QU_wRjBwm5lTFqUAuY/img.jpg?width=1245&coordinates=9%2C114%2C117%2C115&height=700" id="57c44" class="rm-shortcode" data-rm-shortcode-id="738390830a2012a70b3e8f816349edd4" data-rm-shortcode-name="rebelmouse-image" />
Image source: Chris Moody / Shutterstock / Big Think<p>Regarding this theory, Stamets presented "Psilocybin Mushrooms and the Mycology of Consciousness" at Psychedelic Science 2017. In his talk he sought to rehabilitate McKenna's hypothesis as a totally plausible answer to a longstanding evolutionary riddle. "What is really important for you to understand," he said, "is that there was a sudden doubling of the human brain 200,000 years ago. From an evolutionary point of view, that's an extraordinary expansion. And there is no explanation for this sudden increase in the human brain." </p><p>Why not mushrooms? Stamets portrayed a group of early humans making their way through the savannah and happening across "the largest psilocybin mushroom in the world growing bodaciously out of dung of the animals." It needn't have been unusually large to have its effect, of course. In any event, he invited the crowd to suspend their disbelief and admit that McKenna's idea constitutes a "very, very plausible hypothesis for the sudden evolution of Homo sapiens from our primate relatives," even if it's an unprovable one.</p><p>The audience's response was reportedly enthusiastic, though it's fair to note that these were people attending a conference on psychedelic science, and thus pre-disposed toward such chemicals' importance.</p>
Just tripping?<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8xOTM4NTIxNy9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY1NTk3NjE5Nn0._VkcEymkrqEQrAm7locgrXjMGK12Be9cklP25q7zGrY/img.jpg?width=980" id="02596" class="rm-shortcode" data-rm-shortcode-id="a4658fae8f194a86092af9594eba98c9" data-rm-shortcode-name="rebelmouse-image" />
Image source: Apple2499 / Shutterstock<p>Certainly, there's general agreement on the mystery Stamets cited, if not so much on timing details. And consciousness, the "hard problem" even in its modern form, is an area rife with unanswered questions. What <em>is</em> consciousness, anyway? Is it a simple enough thing that it could have a single root cause as McKenna and Stamets say? Many experts suspect our brains gained new capabilities as the result of early community ties and the requirements of social interaction, but when?</p><p>Anthropologist <a href="http://www.iantattersall.com" target="_blank">Ian Tattersall</a> tells <a href="https://www.inverse.com/article/34186-stoned-ape-hypothesis" target="_blank"><em>Inverse</em></a> that the <em>where</em> seems obvious enough: Africa, "For it is in this continent that we find the first glimmerings of 'modern behaviors'. . . But the moment of transformation still eludes us and may well do so almost indefinitely."</p><p>There are other researchers who've studied early humanity's use of drug plants but who are skeptical of the stoned ape notiion. <a href="https://www.researchgate.net/profile/Elisa_Guerra_Doce" target="_blank">Elisa Guerra-Doce</a>, an expert in the field, considers the idea too simplistic, potentially a reduction of a complex evolutionary process into a single "aha" — or maybe "oh, wow" — moment. She's also troubled by there being little evidence of such a pivotal moment, or of drug use at all, so early in the archeological record.</p><p><a href="https://beckleyfoundation.org/amanda-feilding/" target="_blank">Amanda Feilding</a> of the psychedelic think tank <a href="https://beckleyfoundation.org" target="_blank">Beckley Foundation</a> says, however, that the stoned ape theory is at the very least a valid reminder that humans have always been drawn to and fascinated by mind-altering substances: "The imagery that comes with the psychedelic experience is a theme that runs through ancient art, so I'm sure that psychedelic experience and other techniques, like dancing and music, were used by our early ancestors to enhance consciousness, which then facilitated spirituality, art, and medicine."</p><p>Just how early our love affair with hallucinogenic states began may have something to say about the plausibility of McKenna's hypothesis, but, alas, we don't know when that would have been. And, as the saying about the 1960s goes, even if any of these people were still around to ask, anyone who was really there wouldn't be able to remember.</p>
Big and strong? That's not what makes an alpha male, says primatolgist Frans de Waal.
- The cultural notion of an alpha male as a strong, mean aggressor is rampant but wrong. The reality is more complex.
- Frans de Waal notes two types of alpha males: Bullies and leaders. In chimpanzee society, the former terrorizes the group while the latter mediates conflict.
- The reign of alpha male bullies usually ends poorly in the wild. Chimpanzee bullies get expelled or even killed by their group, while leader alphas are somewhat democratically kept in power, sometimes for as long as 12 years.