Science Water Cooler Talk - Evolution and Health

Lot’s going on in the world. In my effort to keep you abreast (and stay a little more on it) here are some elevated, now.

EVOLUTION & GENETICS
Paleobiology is the rage
1. Extinct Woolly Mammoth's DNA Mapped – from LiveScience.com
2. Scientists Sequence Half the Woolly Mammoth's Genome – from Scientific American

HEALTH & HUMAN BEHAVIOR
1. More teens and young adults engaging in anal intercourse – from Scienceblog.com.
Okay, we need to have a serious dialogue with our young people to make sure they comprehend what they are doing and why. This article suggests that many girls who engage in anal sex may not being do so consensually.

2. Exercise increases brain growth factor and receptors, prevents stem cell drop in middle age – from Scienceblog.com
Besides improved heart health, overall physical fitness and staving off diabetes, here is another – and very compelling reason – to NOT be a couch potato.

Later.

Science Vocab: Heritability

Here’s a pop quiz. Read the following statements and select the best answer from the choices below.

A: Snoring runs in my family; it is genetic.
B: Snoring runs in my family; it is heritable.

1. Statement A is true
2. Statement B is true
3. Both Statement A and B are true
4. Neither Statement A or B are true
5. Don’t know

The answer: Only Statement B can be true. Heritability deals with the likelihood or probability of traits running in families. But here is the catch: something can be heritable due to genetics or environment. In this case the environment includes culture or habits and behaviors that you experience and accept as a normal and everyday. Everything that shared among related individuals isn’t necessarily because they share the same genes.

Here’s another snag – heritable traits and inherited traits are not synonymous. To inherit something means you received it or get from your parents. Think about an heirloom. Your grandfather has this amazing fishing pole. When he passes on, he gives the fishing pole to your father and your father gives it to you. You get the exact same thing your father and grandfather had. Genetic inheritance works the same way. One parent has a gene or allele and he or she gives to you.

Heritability is the likelihood of getting something…in other words, you might get it. It’s not automatic – like genetic inheritance, but the chances look good.

Here’s an example: Autism: highly heritable but not inherited
Arthur L Beaudet of Baylor University examined genetic causes of Autism. He found specific gene disorders that can result in autism de novo, automatically or off the top. These disorders include an alteration of the genome causing complete loss of copy, gain of copy or disruption of a dosage-sensitive gene.

But research by Sebat et al. indicates that other genomic deletions and duplications may point to genes in which mutations may lead to autism, but doesn’t automatically cause autism. In other words, having these genes doesn’t mean you will automatically have autism, but your chances are high.

Thinking about human behavior and habits, many of us confuse genetic and cultural heritability, especially when comparing family members to one another. If it’s something positive like – good looks or being smart, then it is thought to be an asset. You feel like you’ve got the deck stacked in your favor. "Natural with no extensions. She get it from her mama."

But all too often we hear people say unpleasant and hurtful things and characterize failure as a family curse. For example, making bad grades or getting into trouble. “You get that bad behavior from your father”. The good news is that these behaviors are NOT genetic, not ingrained in that person. The similarity is coincidental or because of a habit. Habits can be changed. Genes cannot.

Science Vocab: Dulosis - Slave-making in Ants

Ants, like other social Hymenoptera, are some of the most fascinating animals there are. They live in societies – fully functioning, every-individual-has-a-role-and-must-contribute-society. Though I talk about the ups and downs of human societies, animal societies are just as interesting and complicated. Even the unattractive aspects of human social behavior exists among our animal cousins. Dulosis is the slave making behavior of some species of ants.

Here is how it works:

The Parasite species exploits the parent care (brood care) of another species. They steal pupae from another species (the host species). An all-out fight ensues between the species and it is not pretty. Ants die…lots and lots of ants die. If the raiding party is successful they will kill the workers of the host species leaving too few to worry about. The raiding party carry the kidnapped pupae to their nest where they complete their development. The pupae stage is the last metamorphosis. Pupae require no special care for food. It is very much like the cocoon stage of a butterfly.

Days later pupae emerge as fully adult worker ants and accept the Parasite Queen and parasite workers as their own kin and commence with the jobs they were kidnapped to do – raising the larvae of the Queen. Sounds eerily familiar to slave dynamics in the Americas. Slaves were kidnapped from Africa, brought to the New World and forced to work the plantations and females often nursed and cared for the young of the owners.

But like all tenuous relationships, there are is co-evolutionary war at hand. This has and will always occur when two individuals or groups have a relationship but conflicting goals. This, too is eerily familiar.

The host species have some defenses against this colony attack and pupae kidnapping, for a long time, everyone thought that these defenses must all be pre-take-over defenses. And that makes sense. These Pre-take over defenses include enemy recognition and physical defenses (fighting) against the parasites. At the same time, no one really thought that post-taker defenses were possible. For one, once the ants emerge they smell the odor of the colony and imprint to it, and everyone thought this locked everything in place. Plus, no one imagined a scenario of rebellion. What good would it do the kidnapped ants to rebel? They can’t “go back home”. They wouldn’t know where it is, besides, everyone was killed in the battle to take them as pupae.

But according to some research by Susanne Foitzik, rebellion can happen and she has documented it. She studies ant species are found in the northeast United States, Atlantic Region: slavemaking ants Protomognathus americanus and Harpagoxenus sublaevis and their hosts Temnothorax spp. and Leptothorax spp.

Photo of a Harpagoxenus sublaevis– credit: antclub.ru

Photo of a Temnothorax – credit: bugguide.net

Even after the slave ants have accepted their “new home” there have been some recorded incidences that slave workers will actually kill the larvae of the parasite brood they were supposed to raise...but only the female larvae. In some cases slave workers actually attack, mutilate and rip the larvae apart. In other cases, the workers will simply neglect the larvae by not feeding them and discarding them in “dump piles” in the nest. Some host species are more vicious than others with some species more likely to rebelling than others.

Why would this happen? Well the running reason has to do with the fact that perhaps the slave workers are keeping the Brood colony in check. By doing so, they prevent or decrease the number of raids on nearby host colonies that are likely to be comprised of their relatives…a sort of indirect group selection.
But how do they know which pupae belong to which species? It seems the chemical and olfactory cues – hydrocarbon profiles are different for each species; and the slave worker ants can distinguish between the female pupae of their own species and that of the parasite species. However, they cannot distinguish between male pupae of their own or parasite species.

And this is why some think the workers don’t kill male pupae. The proposed answer is believed to be related to odor…male larvae “smell” different than female larvae and some experiments suggest that the male larvae of parasite species smell a lot like the male larva of the host species. Moreover, male ants aren’t considered a real threat. Males don’t participate in colony affairs like work, defense, or raiding other ant species nests. Simply put, males mate, then die.

Addressing Diabetes with Traditional Nutrition

World Ark Magazine is produced by Heifer International, an amazing organization that empowers communities and addresses hunger. In the May/June issue of this year. Healing History is an article (on page 32) about how US Native Americans are re-discovering their food heritage and tackling their major health nemesis – diabetes.

North American Native Americans suffer unusually high rates of diabetes, so much so that being diagnosed with diabetes is no longer alarming. The subject of the article, Paul Smith, a member of the Oneida tribe in Wisconsin, has diabetes along with most of his family.

What’s to blame?

One answer is genetics. Type 2 diabetes does have a genetic component with high rates of incidence among full-blooded Native Americans. As a group, the rate of type 2 diabetes is more than twice as high as among whites.

A second answer has to do with major lifestyle differences of modern Native Americans compared to their fore-parents. Indigenous populations are choosing more wholesome, traditional diets less as fast food and convenience foods become so tempting.
Both of these answers hint to the role the diet and evolution and Thrifty Genes on this ethnic group.

To respond to this crisis, diabetes educators are advocating for a return to Native American diet traditions. Type 2 diabetes in this community is actually a diet-related illness and they are addressing this illness nutritionally. There is now a renewed focus on traditional Native American foods and diets – such as more legumes, fresh vegetables, squash, corn and beans and less convenient and processed foods. By eating like more like their great-grand-parents, today’s Native Americans are actually restoring the balance within their bodies, and improving their health and communities.

Science Vocab: Thrifty Genes

The other day, I hinted about my struggle with weight. Carrying extra weight is not healthy, but for some people shedding pounds is a challenge. It is for me. I blame my thrifty genes for some of my struggles.

The Thrifty Gene Hypothesis was first presented in the 1960's. It basically says that the among some ethnicities, their genes for metabolism work differently.

People from ethnic groups like Africans, Native Americans, and Polynesians evolved in areas where there were routine food shortages, due to extended dry seasons or cyclic famines.

Those individuals who carried a little extra fat -- in the hips, stomach, thighs or where ever --survived hungry times better. They carried more fat because of how their bodies metabolized carbs. Instead of burning it all off, their metabolisms were frugal or thrifty, burning less energy and storing more of it as fat.

I personally think the term Thrifty Genes isn't the best description. I prefer Famine-Resistance Body Type.

Fast-forward to the pro-industrial age.

We definitely have a more sedentary lifestyle than our ancestors. We put less energy into farming, chasing down game, gathering food, and preparing and cooking food.

Also, food is more regularly available - in the Industrialized world, fewer chances of famine and food shortages.

We also have a lot of processed, high carb, high sugar foods - more caloric-bang for the portion size. Those of us who have ancestors who successfully lived in these harsher conditions, but inherited their "good famine-resistant genes" are now at a disadvantage. Our genes and physiology are pre-programed - save more, burn less and there is little we can about it - other than eat differently and exercise more.

This hypothesis is presented as plausible, though not definitive, explanation for why African-Americans, Native-Americans, and Polynesian peoples have a higher propensity for weight issues and health problems like diabetes and heart diseases.

Science Vocab: Sexual Selection

Sexual Selection is the umbrella term for all of those natural forces that influence and shape animal sexual and reproductive habits and outcomes. It is a sub-set of natural selection that deals with one and only theme – SEX. Biologically speaking, you’re only a winner if you successfully reproduce and the one who leaves the most number of healthy and viable offspring.

The truth is there is much similarity between human social behavior and that of our other animal kingdom cousins. This seems especially true when I think about mating behaviors (courtship, sex, and relationship habits). I have read several papers on the subject of sexual selections and thought to myself … “Dang, that sounds an awful lot like the relationship games people play.” And what’s more, you probably know (and act out) a lot more about sexual selection than you ever realized.


Related terms: Intra-sexual Selection and Inter-sexual Selection

Intra means within, in this case the competition of members of the same-sex to get the attentions and affections of an opposite sex mate. Typically, males of the species are the focus of scientific studies of intra-sexual selection. Think back to your science lessons or National Geographic Specials…..
Two male rams, broad and large in size, with impressive horns on their heads are stalking and sizing each other up, then they bolt in a run and Clash! Bump heads with one another. It continues until a winner is determined. The prize: the chance to mate with the female goats and sire the offspring of next season. But there is also female-female competition, but it usually less dramatic.

Inter means between, in this case how the sexes choose one another. In the case of our National Geographic rams, the female goats can decide they like the winner or the loser of the battle or some other male altogether.

So what about us…
Imagine the scene… A night club, music is hot the dance floor is crowded, lots of lovely people in the house. A group of guys are hanging out together and they spot a group of girlfriends kicking it too. Assuming everyone is available for dating here’s what’s happening….

Intra-sexual Selection: The guys, though friends, are all trying to figure out which one of them will probably step up first and what type of game he’ll put down. And these guys are competing with every other guy in the club, too – not just their friends. You’ve got to figure out if it’s worth it and when to step up, check your breath, your wallet, and your rap. The Ladies are doing the same thing and in this case comparing themselves (physically) to every woman in club – adjusting herself, checking makeup, etc. The signals she sends matters and the signals other women send matter. It’s not a big push-and-shove, but it’s a jungle out there.
Basically each person is competing, whether directly or indirectly with every other person in the club of the same sex. Basically, everyone is hoping to get noticed or make eye-contact, share a glance and a conversation that might lead to more.

Inter-sexual Selection: After all of the posing and posturing and adjusting you finally step to that guy or girl. You chose them, but will they choose you…or ask about your friend? That’s inter-sexual selection.

From now on, I’ll routinely share more science info about Sexual Selection and related vocabulary.

Hello, My name is Snarky

I smile with pride with my ability to use my vocabulary to saying cutting remarks about people in their company but that go over their heads. It usually takes a moment (or days) for them to realize that I zinged them. Now, considering I use this blog to explore matters of classism, this is another way to distinguish and reinforce class roles. However, my favorite prey are those so-called Black Middle Class Sheep of which I have a mixed opinion on. I don't doubt alot of my unkind judgements rest on what might be characterized as my own demons -- coming from a working class (poor) background now mingling with these self-appointed VIPs.

But let me rant for a minute. I am often disappointed with how unread and unsophisticated they are. I mean they don't shit about shit -- but they sure look snazzy. And has anyone else been held hostage while they spout off their resumes? I try to remain stoic and professional, but I want to just stop them in their tracks and say "I'm not impressed with you. So, how 'bout them Celtics?" They're vocabularies are fair but not expansive, they think wearing a suit means they are an expert in every subject they witnessed on TV, their travels consists mainly of road trips to Chicago and Atlanta or to the Superbowl or NBA All-Star Game (tickets to game not included) and all of the clubbing and partying a 20 & 30 something can handle. Many don't have passports, don't speak a foreign language or have friends from other cultures. I mean, how does one consider himself so 'cosmopolitan' with such a lack of experiences?

I've always been a smart ass, a sassy mouth, sardonic. I often spoke words that were judged as disrespectful, rude or speaking over someone's head -- even as a very young child. I probably was punished more for my remarks than my mischievous actions. So imagine how amused I was to discover that Sarcasm is Seen as an Evolutionary Crucial Skill. How 'bout them apples?

Weekly Science Update - Breakthroughs in Evolution

I like how the New York Times, the LA Times and USA Today, and even Yahoo! News each has a science section and it includes stories about ecology, nature, health, medicine, even science-society intersections. Why haven’t Black Media outlets done the same? Well, until it happens, I’ll continue posting important and interesting information about science and research. Think of it as supplemental News. The weekly science update labels are a quick way to see what’s new in Science and Research. And if you don’t listen to NPR Science Friday -- you may be even further behind than I think -- here is your Crib Sheet for Cocktail party talk this weekend. Both are rather quick reads. So scan through them quickly impress everyone with your knowledge of evolutionary theory over drinks. This week’s theme – EVOLUTION.

Platypus Genome Decoded Yes, this is a big deal. Okay not the “how does this apply to me” kind of way. But it’s a big deal to evolutionary and conservation geneticists/biologists. Yes, the freaky looking platypus’ genome has been figured out. And yes, it confirms what every elementary kid thought when they first are introduced to this animal - Platypus DNA is a combination of reptiles, birds and mammals; but in the most evolutionarily delicious way. Check out the story.

Ancient "Nutcracker Man" Challenges Ideas on Evolution of Human Diet Short and sweet – Anthropologists examined the tooth wear and food residuals of early hominid teeth. Usually dental paleontologist use ancient teeth to hypothesize what animals could eat. Because of this hominid’s tooth, cheek, and skull structure, plus the tell-tale wear on the teeth, they surmised that these early humans were well-suited for eating nuts and fruits with hard shells. But thanks to better digital and electronic imaging technology that can take a closer look at the teeth and determine what they actually ate (or more likely to have actually eaten). Neat, huh?

Oh, and don’t forget my prior posting on Human origins in Africa are derived from 2 lines.

Knock ‘em out.

Evolution Debate - Science vs. Faith

The Debate about teaching Evolution in Science Classes and whether to include lessons about "alternative" theories has been a matter of science education contention forever, it seems. Feb 29, 2008 issue of Science magazine reported that Florida Standards Support Evolution--With a Twist.

One of the main counters to teaching evolution is a semantics issue. The word theory ties counters' panties in a knot. In lay terms, a theory is a guess, a whim. But in science, it is a firmly supported statement (hypothesis) that has withstood strong contests. A theory is a big deal, it pretty much set and that's it. For example, gravity is a theoretical concept (of physics), the Law of energy conservation is 'just a theory'. So when anti-evolution legislators in Florida wanted to undermine science education standards and dupe the public into thinking evolution was just sample fancy theory and tried to legally change the text books to say "evolution is a theory", suave scientists and science educators complied...Fully. They changed the language through out to make it parallel. They applied the phrase to every major, time-tested scientific concept. So not only is evolution explained to be a "scientific theory of evolution" but also things like "the scientific theory of photosynthesis".

Gotcha!!

But this matter is serious. Religious zealots are serious about undermining quality science education. Why? Many reasons, one of the best answers comes from a Florida legislator who tried to re-word the science standards for evolution, Donna Callaway. She says "People have asked me why I don't question math concepts or grammar," she explained to Science. "I tell them, 'Those things have nothing to do with life. Evolution is personal, and it affects our beliefs.' "

My response to that statement....WOW. That is naive. Plus, that's apple-picking. Even Nisbet commented on this issue in his blog posting Why the PZ Myers Affair is Really, Really Bad for Science. I completely share the sentiments of this blog. In fact I was having a great discussion with a friend about evolution distorting people's spiritual beliefs. I think it is crap to assume studying science makes one more likely to become atheist. I just don't buy that evolution affects our beliefs -- assuming one understands the concept. That's the problem. Too many people are guessing what they think it means. And what makes it right for some people to tell us what is right to impact out beliefs. I guess studying science is heresy -- leads to critical thinking, discernment, challenges to authority. Damn independent thinkers. Can't have that. Let's protect them from themselves...Change the science standards.

But for many people (outside of science) it seems a plausible correlation. Many of my peers are atheist, agnostic, or spiritually neutral. But none that I know are that way because of studying science. They were that way long before studying science. And I also know scientists of faith, who were also that way before studying science. Go figure.

Is there a relationship between science and atheism? Perhaps. But you can't automatically conclude it is causal.

Do you have a sweet tooth? There is a reason why.

Food Science and Nutrition Science explores not only the the importance of food in our lives, but also the history of food and human nutrition evolution. A recent article on LiveScience.com has a very interesting article about our (humans) affinity to sweets: Why We Love the Sweet Life.
A preference for sweets may have been favored and selected to aid our primate ancestors to find ripe, nutritious, energy rich fruits.

Crazy Mutated Monsters - A lesson on evolution

With all of the hoop-la about genes, genomes, cloning and etc., I thought this link this New York Times op-ed about random mutations was interesting.

In short, some propose that during the very early embryo stage some can go all hay-wire in the genomes. Usually if the embryo is all jacked up, then it doesn't survive. It is reabsorbed, expelled, nixed. But what if this mutated embryo makes it and develops okay and is born/hatched, etc.? And just maybe this weird thing is actually a superstar in its environment. And it reproduces? Well that's a new successful organism. Ta-dah.

But that's not typically how it goes. But, the neat thing about science, and what makes genetics and cellular biology so great, is that all the new technology and things we're learning about genes and the genome is still so new. Stay tunes