Hi folks, Our next chapter (for Thursday) covers learning and cognition in animals, and I wanted to offer a couple of supplemental readings to accompany the material in our text. Our textbook describes a bit about the extent to which our closest relatives (the other members of the "great ape" lineage) may possess mental faculties approaching our own, and these two readings expand upon that idea, with the caveat that we may not also know how to best test, or interpret, animal behaviors. The first reading describes some of the work done by researchers at Kyoto University, which houses a rich group of researchers in primate cognition. This report describes an attempt to interpret the mental states of chimpanzees, based upon their reaction to stimuli. If animals possess the capacity for thoughts and behaviors related to traits like empathy, jealousy, or disbelief, we can predict that they may respond in specific ways to certain kinds of stimuli. It's a challenging argument, to be sure, but many in the primate community believe that our closest primate relatives share more of our "higher" cognitive abilities than many would care to admit. https://www.scientificamerican.com/article/chimps-may-be-capable-of-comprehending-the-minds-of-others/ The second reading is from a prominent primate behaviorist (Frans de Waal), who has long argued that we approach animal behavior too simplistically, and often erroneously. Taken to an extreme, he suggests that, at least at times, we are testing the wrong things and making interpretations that are illogical. I do not believe that his interpretations are widely held by members of the behavioral community, but they do serve as a useful reminder that we often make too many assumptions in our design and interpretation of behavioral experiments. https://www.wsj.com/articles/SB10001424127887323869604578370574285382756 When we delve into Chapter 07 on Thursday, it will be useful to keep these viewpoints in mind. See you this afternoon for collection of exam corrections. We'll have time to review and discuss any material we wish to cover today. Sincerely, Dr. Nealen
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Good morning all, We recently described human blood in lecture, noting that it is red in color (of course!), and that its color comes from the hemoglobin pigment inside of our red blood cells. How about a person whose whole blood is blue? In the news this week is a report about a woman who used excessive amounts of a common over-the-counter analgesic (benzocaine) which rendered her hemoglobin blue in color: https://www.cnn.com/2019/09/19/health/blue-blood-trnd/index.html Persons of low blood oxygen levels are considered to be 'cyanotic', and often have a pale or bluish cast to their skin. If their hemoglobin has been poisoned, it can impair oxygen transport/delivery, at worst, to a fatal degree. In this case, the blue color was not physiologically problematic. This woman's blood was still relatively high in oxygen content, but contained more cyanomethemoglobin (which causes the blue color) than is normal (few percent). Luckily for this woman, her problem was cosmetic only, and the antidote (ironically, doses of methylene blue) was both simple and effective. Interestingly, blue blood is perfectly normal in crustaceans (such as crabs and lobsters), because they employ hemocyanin (rather than hemoglobin) for oxygen transport. Their blood is of such great medical utility for testing of toxins and contamination that a large (and controversial) industry is devoted to its collection: https://www.theatlantic.com/science/archive/2018/05/blood-in-the-water/559229/ And, there is a known genetic disorder than causes cyanosis to run in (a small number of) families, including the famous 'blue Fugates of Kentucky': https://www.iflscience.com/health-and-medicine/the-science-behind-the-mysterious-blue-people-of-kentucky/all/ So, the next time you hear the term "blue bloods", you might wonder if it is genetic, pharmaceutical, or crustacean in its basis... Have a great weekend - Dr. Nealen Good morning all, We recently considered bat echolocation as a model for sensory coevolution. During our discussions, we noted that many animals have sensory capabilities outside of the range of humans. How about humans who can perform echolocation? https://phys.org/news/2018-04-humans-echolocation.html There are a small number (few dozen) people in the world who have developed some level of proficiency at echolocation for navigation. Daniel Kish is the most famous person with these abilities (but there are others): https://www.youtube.com/watch?v=A8lztr1tu4o In all of these cases, the ability came about after a loss of vision. Our human visual cortices make up a huge part of our brains, and once they are freed from visual responsibilities, it seems that they can be co-opted (at least in part) for other uses. This neural flexibility is well-known, as it is the basis for the recovery that is possible from brain trauma, including stroke. Blind persons who read Braille are known to have some expanded touch sensitivity in visual areas of the brain, and sensory re-mapping is known to occur in persons with high-levels of musical training, or in new mothers nursing infants. Still, the development of echolocation as a sensory capability is quite different, in that it adds to the human sensory repertoire, not simply expands upon an existing sense. There are lots of interesting articles about human echolocation, including: https://www.sciencealert.com/humans-can-echolocate-like-bats-and-whales-and-we-ve-finally-figured-out-how-it-works https://www.livescience.com/39231-humans-can-learn-to-echolocate.html https://www.newscientist.com/article/2145962-this-is-how-some-blind-people-are-able-to-echolocate-like-bats/ Next time you find yourself in a dark room, you might be tempted to give it a try! I think that I will stay close to the light switch... Have a great weekend - Dr. Nealen Your Environment Is Cleaner. Your Immune System Has Never Been So Unprepared. - The New York Times9/19/2019 Good evening everyone, At the end of this week we find ourselves in the midst of a discussion of immune function, first with our lecture yesterday on the immune system (Chapter 7), to be followed by our next lecture on infectious disease (Chapter 8), scheduled for next Monday. Recall that for tomorrow's class (Friday 20 Sept), we will not meet in person. Instead, I'd like you to read/digest a news article on a current and very relevant immune topic, that of environmental exposure to antigens. For much of the history of our species, human life and society was based around agriculture, including exposure to domesticated animals. In the last hundred years, of course, that has changed for many, as populations became more urban. During this same period, the use of cleansing and sanitizing products in the household has increased dramatically, culminating recently in the explosion of "anti-bacterial" products, such as soaps, wipes, and tissues. Most immunologists believe that we have taken cleanliness a bit too far. According to the "hygiene hypothesis", natural exposure to antigens keeps the immune system primed for action, and enables it to make robust responses to actual disease agents. In our ultra-clean worlds, however, many (especially the young children of cleaning-obsessed parents) are coming into contact with fewer and fewer natural antigens, and increasingly their immune systems are ill-equipped to respond to them when they do, leading to a rash (no pun intended) of allergies, sensitivities, or, at worst, autoimmune disorders. This article explores the "hygiene hypothesis" and some of its implications. As you go through it, I'd like you to consider a few key questions: - what happens to our immune system when we are exposed to naturally-occurring antigens? - why should exposure to non disease-causing antigens enable us to better respond to more serious antigens? - do you personally use anti-bacterial products in your household? - does this article make you want to reconsider their use, in any way? https://www.nytimes.com/2019/03/12/health/immune-system-allergies.html?searchResultPosition=19 Our immune system is wonderfully complicated and powerful, but some think that our social behaviors have evolved faster than is good for it. Perhaps a nice walk outdoors, a swim in a lake, or a picnic in the grass is just what we need... #ReturnToNature Have a great weekend - see you on Monday. Dr. Nealen Good morning everyone, We soon will be discussing the brain and nervous system, and our discussions will include the concept of 'body maps' in the brain. These represent areas of the brain that contain neurons that are spatially arranged to correspond to particular areas of our bodies (like our fingers and faces). We all have them, and they make some of the computations required by our brain a bit easier. Specialized training (such as the playing of a musical instrument) can modify these maps, making them (in some case) larger and more sensitive. In the science news this week is a report about these brain maps, but in an unusual way. This news describes brain maps that represent the fine motor skills one develops as a painter, but with a catch: these are painters who use their feet, rather than their hands. In these subjects, the 'brain maps' for their feet have been come elaborated, much like what happens to the brain maps for fingers when highly trained to perform a skill like a painting. This story reminds us of a number of important features about the brain: even in adults, much of the brain is 'plastic', or modifiable - that is the secret to our ability to learn new things. This story also demonstrates the old saying the 'nature abhors a vacuum' - if part of the brain is not being used a its normal task, in some cases that task can be shifted elsewhere, and parts of the the brain 'reassigned' (to some degree) to new responsibilities. This flexibility is also a hallmark of our brains, and is an important one, for it contributes to recovery from brain injuries, like stroke. When areas of brain tissue are damaged, in some cases nearby areas can be trained to take over those functions that are no longer being served. So, even if you find that painting is not something you are good at (as I have), don't despair! You have plenty of brain tissue ready and waiting for your hidden talents to emerge... https://www.sciencenews.org/article/artists-paint-feet-toe-maps-brain Have a great weekend - Dr. Nealen Good morning everyone, In my scans of the science news, I often come across articles that overlap with our course topics. I'll share some of these with you, in the hopes that you find them interesting, and with a goal of broadening our conversations. Today's news comes from a report about animal-based espionage, via training programs conducted by the CIA during the height of the Cold War. Animals are often highly adept at trained behaviors, and instinctual behaviors (like homing) can be co-opted for specialized tasks. Still, this report suggests that there was little direct benefit from these programs - or, perhaps they are not telling us everything, as much remains classified. So, the next time you see a pigeon, cat, or dolphin(!) nearby, remember: they may be watching you as well... https://www.bbc.com/news/world-us-canada-49692534 Have a great weekend - Dr. Nealen Good morning all, As a follow-up to the news article I last sent, here are a couple of updates on this developing story: Severe illness and unexplained deaths associated with vaping have continued to occur, and, while no definitive cause has been identified, the majority of cases seem to be linked to the inhalation of vaping substances that are coating or irritating the lining of the lungs, preventing proper gas exchange. Vaping materials often have additives, such as flavorings or oils, that are the prime target. A number of persons suffering respiratory distress after vaping seem to have oils lining their lung surface. As one researcher put it, 'The lungs are designed to encounter gases only. Inhalation of other substances is inherently risky'. https://www.nytimes.com/2019/09/07/health/vaping-lung-illness.html https://www.washingtonpost.com/health/2019/09/07/what-we-know-about-mysterious-vaping-linked-illnesses-deaths/?tid=pm_national_pop I understand that vaping is quite popular, and I worry (a lot) about how dangerous it is. It is trendy and new, but not well regulated, and too recent to have been well studied. I suspect there will be much more news on this topic, and likely soon many more regulations about what can or cannot be included in vaping materials. I hope that you do not vape - but if you choose to do so, please be informed, for your own safety. Sincerely, Dr. Nealen Good morning all, Just passing along here an interesting news article, linking behavior and conservation. Human have long associated with animals, and in doing so have shaped many of their behaviors. Here's an example of a detrimental effect: a semi-domestication that changes foraging behavior and seed dispersal in endangered New Zealand weka: https://www.nytimes.com/2019/08/29/science/weka-birds-seeds-new-zealand.html This kind of change illustrates the behavioral flexibility many species employ, particularly for adapting their own ecology to exploit the humans around them. In the long run, these sorts of associations can cause evolutionary change in brain and behavior (https://www.nationalgeographic.com/animals/2019/09/humans-shaped-dog-brains/), in ways that can dramatically alter the natural ecology of species. This is also an important reminder that interacting too much with endangered species can endanger them ever more if they imprint too strongly on humans - hence the need for 'panda suits' (https://www.youtube.com/watch?v=GaLP6S9ZHQ4 - how's that for a day job?). See you tomorrow for review of the material for our first exam. I'm not planning a formal lecture; instead, I will review any material on which you have questions. Sincerely, Dr. Nealen |
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