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Chr
18 February 2011 @ 06:18 pm
Should physical education in schools be mandatory, and why?

Okay, replying to this really quickly, because this topic was discussed in my "Mind, Brain, and Education" course last semester.

Physical education should definitely be mandatory all the way to post secondary. Physical exertion, even if it's just walking for thirty minutes, has been shown to significantly improve memory, attention, and overall cognition. From an educator's point of view: if all students participate in physical activity, school-wide test scores should improve. (Though, clearly, some students would show larger benefits from this than others.) And this is not just an acute effect; one bout of exercise can improve performance for several days, so physical education courses could be staggered with academic courses to maximize the benefits of both.
Of course, this brings up gender concerns, because girls are typically active for only half (or less!) the time boys are active in any given physical education class. And even then, for one hour-long physical education period, male students typically spend only 30 minutes actually BEING active. (I don't know who thinks to conduct studies like this, but they're really brilliant.)

And of course; "obesity epidemic," heart disease, dementia, etc.
 
 
Chr
30 October 2010 @ 10:57 am
First: Four year old uses her bike to murder an 87 year old woman.
Um... lolwut? I completely disagree that four years and nine months old is old enough to use critical thinking and reasoning skills. Children at this age BARELY use their frontal lobe for decision making (the frontal lobe is used for higher order thinking, like empathy and resisting biological urges, and fine motor movement). Also, I doubt she was very proficient at riding her bike at that age, because children just do not have highly coordinated motor movements before extensive training and brain maturation. (This is part of why the physical act of writing is difficult for young children.) Also, the last quote by the judge, while I'm leery to interpret it out of context like that, sounds like he's implying the child hit the old woman on purpose. Unless the kid has antisocial personality disorder, this seems a bit unlikely... AMERICA, STOP BEING A DOUCHE.

And while we're on the topic, to the guy on the school board (and the other guy running for some sort of political office) who said church and state should not be separate: Please stop wasting America's medical resources by visiting doctors and getting vaccines. You are harming society by repressing science, critical thinking, and basic human rights, and using the products of the labours you oppose is hypocritical and a waste of our resources. Thanks. (Unfortunately, I do not have a link to either of these stories, but I'm sure my American friends can think of many people these men could be.)

Second (or third, whichever): Another biodiversity summit fails.
Oh, we are SHOCKED. Why would I give up the money I have right now to make tons more in the future? I mean, I might not even be alive then! And screw my children having health and prosperity (not to mention the general happiness that nature can provide (srsly, being in nature has been shown to greatly reduce stress and improve overall health, never mind the value of natural resources and services)); that doesn't benefit me right this very second, and when they're older they'll fix anything we destroy.

In related good news, though, Iberian lynxes are making a nice comeback after some intensive conservation and captive breeding efforts. (Though please keep in mind that many, many animals do not survive in captivity, much less breed. And many animals which do breed become incapable of surviving in the wild after only a few generations.)

Some day I will post my opinion on society relying on zoos for genetic conservation. (Hint: it's very BAD.)
 
 
Chr
10 October 2010 @ 10:37 am
Man, I am so good at this blogging thing. =P

So BATS. They're pretty fantastic; the only known flying mammal that's ever existed. They also have (I believe) the largest order of any mammal. They developed flight very early in their evolution, and not much has changed since then.
There are two primary ways to produce echolocation sounds: internal production with a modified larynx, and via tongue-clicking. Tongue-clicking is generally considered to be the more primitive method. However tongue-clicking bats have longer-range than other echolocating bats (most bats can only identify potential prey from 5m away or less).
What's really cool about echolocation is that every species does it slightly differently. They may use a different pitch or different pattern, but this difference between species allows us to identify an individual down to species without having to capture it. This technique has also been used to discover several cryptic species. Cryptic species are species which look so much like another species, they're often classified as one. Usually after we have a hint that what we think is one species may actually be two, we're able to identify minute physical differences so we can describe the new species.
And while we're on the topic: not all bats echolocate (like flying foxes, for example), and most have very good eyesight.
 
 
Current Mood: amusedamused
Current Music: Assemblage 23 - Divide
 
 
Chr
09 February 2010 @ 09:12 am
There's a line of thinking in ethology (and more rarely in psychology in general) that states that all behaviours can be broken down into appetative or consumatory behaviours. Consumatory behaviours are pretty much any behaviour that is an endpoint of an action, like eating or sex. Appetative behaviours are any actions that lead to an endpoint, like foraging or courting.
This line of thinking used to be very prominent and was used to explain most any behaviour, however it has recently fallen out of favour. It is clear that not all behaviours can be lumped into these categories, since some behaviours, such as play, could be considered either directly consumatory (e.g. playing is a benefit in and of itself) or they may be an extremely extensive appetative behaviour (e.g. playing when young leads to better hunting/foraging and social skills as an adult). But since these behaviours must, by definition, both coexist and appetative must directly lead to consumatory behaviours, forcing behaviours to fit into these categories is nonsensical.
Appetative and consumatory behaviours are now most frequently used to describe behaviours concerning sex and feeding. For sex, different parts of the brain control appetative acts than consumatory, so it is possible to stop an individual from pursuing sex, however when presented with a receptive mate that offers no need for courtship, this individual will still mate. That is, they will not necessarily desire to mate, but they will when given the opportunity with no resistance by their partner. Likewise, it is possible to stop an individual from being able to mate, the consumatory aspect, though they will still be willing to pursue and court a partner, even at great cost to themselves.
Furthermore, appetative and consumatory sexual behaviours may not be regulated by hormonal concentrations, or there may be a very loose correlation. For example, after castration, some non-human, primate males will immediately cease mating, while others may go years before they stop attempting to copulate. Individuals which tend to mate less frequently tend to lose their ability to copulate most quickly after castration. Even when castrated males are all given the same amount of testosterone to reinstate their mating behaviour, they only return to their copulation levels previous t castration. (That is, male who copulate very infrequently still copulate infrequently and males who copulate much more frequently still copulate much more frequently.) This is an important finding because these animals are given identical levels of testosterone, yet they do not react equally. This supports the idea that hormone levels alone do not determine mating behaviour and that there are pre-existing individual differences. These differences are likely due to individual differences in the number of hormone receptors in target tissue.
 
 
Current Mood: busybusy
 
 
Chr
10 December 2009 @ 05:44 pm
Humans are the only organisms considered to have true language. The only other animals that come closest to having a true language are song birds. This is not to say that many animals do not communicate verbally or otherwise, and some animals may even have more complex language characteristics such as deep syntax. What separates human language from other animals' is the symbolic nature of our languages and how we are able to describe an indefinite amount of situations and ideas with a limited vocabulary. No other animal is able to express abstract thoughts such as past or future events or imaginary situations outside their own experiences.
Language learning in humans is innate. Song birds are the only other organisms who will create their own languages if isolated from a social model. Furthermore, humans are limited in the ways they may learn language, and this specificity allows us to learn much more easily than if we had to learn each new word, tense, and sentence structure independently. For example, young children know how to turn a statement into a proper grammatical sentence even if they have never done so before. (E.g. "Ask if the man who is wearing blue shorts is playing basketball," yields a response of, "Is the man who is wearing blue shorts playing basketball," and not, "Is the man who wearing blue shorts is playing basketball?" This is contrary to what would be expected from a simple rule such as placing "is" at the beginning of a sentence to create a question, despite how this is the most common means of converting statements into questions.) This genetic priming is also supported by the fact that all languages are structured either: Subject-Object-Verb, Subject-Verb-Object, or Object-Subject-Verb and that 96% of all languages place the subject before the object.
There are some genetic disorders which inhibit language learning. These disorders frequently inhibit the learning of tenses or the ability to modify root words, such that each new form of a word must be learned entirely independently. So instead of learning that adding -s or -es to the end of a word will indicate there are more than one, effected individuals must learn singular and plural words independently as well as when to use them. Individuals with this type of disorder are generally extremely socially inhibited, despite the fact that many may have otherwise normal cognitive abilities.
Language is extremely important in humans and it likely evolved as a sexually selected and social trait. Since both males and females invest large amounts of resources in their offspring (though females generally do invest more), humans show mutual mate choice. This means that both males and females are choosy about who they will mate with. (Though females are again more choosy.) Evidence suggests that language evolved to be flamboyant (indicated by the fact that the average person uses only a few hundred words in everyday conversation but may actually KNOW around 60,000 on average), and that this likely developed as a way for males to attract mates. However, being clever enough to create, learn, and use language is only useful is females are able to understand what it is you're doing. So females have also been selected to learn language so that they may be better able to judge which males are the most intelligent.
Language has also evolved as a form of social bonding. As human group sizes increased, so did the need for methods of social bonding besides simple grooming. While chimps spend around 20% of their time grooming each other in groups of 15-20 individuals, early human societies contained 50-150 individuals and humans would have had to spend 70% of their time grooming to maintain tight social relations. Language serves as a means of maintaining social relations while also attending to other tasks such as foraging. Support for this comes from the fact that 2/3rds of conservations are composed to gossip instead of explicitly useful topics such as instruction.
 
 
Current Mood: busybusy
 
 
 
Chr
22 October 2009 @ 09:23 am
Fun Fact!: Octopi have photo receptor cells on their tentacles which allow them to "see" their environment with their bodies and mimic it almost instantly. This means that even blind octopi can camouflage themselves almost flawlessly.

Also, I'm in the middle of midterms and have a ton of papers and projects to work on as an added bonus. So, busy, busy, busy! Is there anything in particular you'd all like me to preach about? If not, I might just start posting random facts for the next week or so. (Or the rest of the year. Whichever.)
 
 
Current Mood: busybusy
 
 
Chr
06 October 2009 @ 10:38 am
Humans find symmetry among other humans attractive. This has an evolutionary origin (which is pretty obvious, when you consider damn near all animals find symmetry attractive, and many choose mates based solely on how symmetric they are) which is actually based on fetal development. When a fetus is developing, ideally it should develop to be completely symmetric, however any environmental disturbances can harm fetal development and cause slight (or severe) asymmetric development. Therefore, when someone is very asymmetric, there's also a likelihood that they have slight internal defects as well, which may harm their health and make them a poor mate. Also, this may be an indication that their mother (and possibly their father, in species which raise their young in pairs or groups) was not particularly well adapted to sufficiently avoid deprivation or harm during pregnancy. Since this is likely caused by genetic factors, an asymmetric organism is less likely to produce healthy offspring.
And then, of course, there's always the problem that symmetry is very useful for many species. For example, a fly could not fly as well with two uneven wings as it could if they were identical, which puts it at a competitive disadvantage.
 
 
Current Mood: busybusy
Current Music: MC Fontalot - Diseaes of Yore
 
 
Chr
15 September 2009 @ 09:34 am
Classes started last Thursday, but we haven't really learned much yet (as is expected during the first class). In my animal behavior class, we're discussing the different levels of analysis. I think it may be very useful to explain this concept here, since many laymen (and scientists, too) are not aware of or do not consider this when examining different hypotheses.

The classic example of overlooking analytical levels is the "nature versus nurture" debate. Now it's widely accepted that both DNA and environment impact how one behaves. Also, BOTH DNA and the environment are 100% responsible for every natural characteristic of an organism. (So IQ isn't 70% genes and 30% environment; it's 100% genes and 100% environment, since they work on each other.) My professor made the analogy of making a cake: is the recipe more important or the ingredients? Both, clearly; you have to know what to do and you have to have the materials to follow the recipe to get a cake. Likewise, you can't have 50% of a recipe and 50% of the ingredients and still be able to make a cake; you have to have 100% of both.

Thinking of a trait from an evolutionary level of analysis (AKA, why does this animal have this trait at all?) is called the "ultimate" level of analysis. Considering a trait from the individual/immediate level of analysis is called the "proximate" level of analysis.

Example: Why do birds sing?
Proximate level: Birds sing to attract mates and to defend their territory.
Ultimate level: Birds sing because they've evolved so changing day lengths increase their androgen production, which in turn alters their brain chemistry causing the areas of their brain responsible for song production to grow or shrink seasonally (this actually happens; it's really cool) while also altering their vocal muscles, etc. (My friend is borrowing my notes on bird song production, so you'll have to forgive this lackluster explanation. =[)

As you can see, both of these explanations can (and ARE) true. Furthermore, they interact in a way that evidence for one may be applicable to both. Birds developed photoreceptiveness (photoreceptivitiy?) because it caused them to sing, and singing increased their chances of getting a mate, and getting a mate caused photoreceptiveness to be positively selected for evolutionarily. Evolution leads to a behavior which, in turn, leads to more evolution and more behaviors. It's a nice, cyclic process.

So next time you see an article saying, "IQ found to be mostly genetic," you can call bullshit.

Also, as a quick side note: many people use heritablility as an estimate of genetic impact on a trait. All heritiability determines is plasticity, or the possible range of a trait. (Example: You may have a possible IQ of 100-115 (this can be estimated by looking at your close relatives), but what your actual IQ is will be dependent on environmental factors.) In practical terms, heritability is just a way of predicting how likely it is an individual will develop a trait expressed by their close kin.
 
 
Current Mood: anxiousanxious
 
 
Chr
Rat-Eating Plant
Summary: A pitcher plant was discovered in the Philippines that is so large and complex, it can trap and digest rats! Natural selection at its best, people.
I have to wonder by what mechanisms these plants are able to retain the rat. It seems like a rat would be able to either climb or chew their way out of a plant pretty easily. Maybe it has a mucus coating inside or some type of toxin to dull the rats...

Ancient Squid
Summary: A perfectly preserved squid was found in Wiltshire. This is AMAZING, because soft tissue is insanely hard to fossilize and almost never occurs naturally outside of very large bones. (We've just recently discovered we can crack open well-preserved dinosaur bones and find soft tissues to extract DNA.) This squid was so well-preserved that the scientists were able to crack open the ink sac and use the ink inside. (I assume they had to add water, but that's still crazy.)
I don't really have much to add to this. It's just wow. I hope they'll be able to get some DNA from it; it might shed some light on their evolutionary history.

Glowy Worms
Summary: Several bioluminescent, aquatic invertebrate species were recently discovered off the west coast of the US. When agitated, these worms can shed bioluminescent chunks of themselves from around their gills, and this may serve to distract predators.
Watch the film of the worm swimming; it's adorable. If this species really is so prominent as the researchers hypothesize, then I have to wonder if we're not finding them because we haven't been looking or if we're only finding them now because they're migrating to places we DO look due to global warming. There seems to be quite a bit of species migration lately, particularly in the oceans, where humans can't really restrict travel. I wonder what sort of global impact this will have on species diversity, or if we'll just cause the extinction of most species regardless of where they live or with what other species they compete.
 
 
Current Mood: tiredtired
 
 
Chr
15 August 2009 @ 02:32 am
Classes don't start for almost another four weeks, so I figured I'd discuss some politics in the meantime.

There is an absolutely astronomical gap between anyone studying science and laypeople. While an electrician could probably discuss their work with the majority of people without the listener getting too lost, a molecular geneticist or an astrophysicist could not. The main reason for this isn't that these topics are necessarily much more complex than what an electrician or mechanic would face (though some may require more talent, work, or determination), but it's actually due to the volume of information one has to know to deal with even a simple problem in science. Everything in nature interacts and all these interactions must be accounted for. (Something broad like psychology has to also account for neurology, physiology, evolution, ecology, chemistry, physics, and mathematics (though mathematics and physics will usually be encompassed by chemistry for practical reasons). And statistics is the life-blood of science, of course.)

By definition, a layperson is anyone who is not educated in a certain field. So I'm a layperson to physics and geology and baking, for example. People take this term as an insult, as if scientists or whomever say it to imply that the average person is stupid. But that's not at all what it's about. It's just used to express that said person is not well learned in whatever field and that their opinion is uneducated.
Believe it or not, an uneducated opinion IS WORTH LESS than an educated opinion. (There's a social construct that says all opinions are equally important, but that's crap.) If a doctor tells me my appendix is ruptured and I need to have it removed, I'm going to listen to the doctor over my landlord who thinks I just have cramps. On the other hand, being educated in one subject does NOT make someone an expert in all fields. If someone with a PhD in English literature and 40 years of teaching experience says that the closest living relative to whales is dugongs, I, as a biology undergraduate student, would be able to correct them with more authority on the subject, because I've actually studied evolution. (And if we were discussing literature, they could hand me my ass.)

Science has to account for ALL the information gathered through ALL TIME. That's why scientific theories change. Creationists like to say that science is inconsistent and that makes it unreliable. But science is NOT inconsistent; it's just constantly improving. All hypotheses and theories are designed so they can realistically be proven wrong (they make predictions, and if the predictions fail, the theory is wrong). If we test those predictions and find them to be wrong, then we have to come up with a new theory that explains ALL THE OLD RESULTS and the new ones. Afterwards, the rest of the scientific community gets to test the hell out of the new theory before it becomes accepted. And then everyone tries to prove it wrong and find its limitations until eventually they do and it's modified again or replaced by a new, better theory. (And Creationists like to say people who "believe" in science are dogmatic... =P)
Since science covers such a massive amount of material and changes so quickly, it's literally impossible to keep on top of all of it. This is why scientists specialize in tiny, little pieces of an issue, like the morphology of bivalves in the great lakes or how mitochondria communicate with a cells nucleus.
The more science progresses, the more ridiculous it is to think the average individual could hold an educated opinion on any of it. There's just too much foundation required for a basic understanding, and it's just not practical to expect anyone to know it all.

Most people are not harmed by not knowing how evolution works on a molecular or even global level. However, many, many people are harmed when these uneducated people's opinions are given equal weight as those of experts. My landlord should NOT get a vote in whether or not my appendix should be removed, and politicians and religious leaders should not have a say in what science should be taught and what research should be conducted. That is what teachers and ethics boards are for.
Uneducated intervention and regulation STOPS PROGRESS. When scientific progress stops, the rest of the world keeps going and we suffer for it. (Just look at what happened when we thought penicillin was a cure-all that would always work, so we stopped trying to find cures for many diseases! Drug-resistance, anyone?)
 
 
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Current Music: Blink 182 - Time to Break Up