Old Biophilia

What are your memorial day weekend plans?
May 30, 2010, 5:28 pm
Filed under: Human biology, Student post

by Guest Blogger and Bio 185 Student: C. Lauren Loban

Does moderate alcohol consumption in women lead to a smaller waistline?

In a study originally published in the Archives of Internal Medicine, researchers may have discovered a link between drinking alcohol and maintaining a slimmer waistline. This study from Brigham and Women’s Hospital in Boston was conducted over a period of 13 years and followed almost 20,000 women, all of who began with healthy weights. The study showed that moderate amounts of alcohol might curtail weight gain in women over time, specifically 30% less likely to become overweight or obese. However, “moderate” drinking should be clearly defined for women, as many women may create their own interpretation from this study of what “moderate” drinking is. The small amount that researchers discovered may cause women to gain less weight as compared to those who drank no alcohol at all was the equivalent of one to two drinks per day. Red wine had the greatest association with lower weight, while the effects were also found for white wine, beer and spirits.  However, an example of one drink is considered a 5 oz glass of wine, and many restaurants and bars serve glasses of wine much larger than 5 oz, so it is easy for women to miscalculate how many calories they are actually consuming. It may also become easier for women to justify their drinking habits if they believe it will keep them trim, however it is important to consider the other lifestyle habits of those who drink regularly.

The common characteristics of those who imbibe regularly are essential details of the study, and are very likely linked to the effects of moderate alcohol consumption on body weight. Women who drink moderately are also more likely to consume fewer calories from food, exercise more, have less healthy diets and perhaps not surprisingly smoke cigarettes. So, in the long run of overall health, who is going to win, the moderate drinker-smoker with a lower body mass index who eats less amounts of unhealthy food, or the non-drinker who eats healthfully and doesn’t smoke? My vote is for the latter, or even better –mindful, healthy sensible eating coupled with moderate exercise topped off with a small glass of red wine!

Read more here: http://articles.latimes.com/2010/mar/09/science/la-sci-women-alcohol9-2010mar09

Sound promotes coral growth?!?!
May 27, 2010, 12:35 am
Filed under: Diversity in the animal world, Student post

by Guest Blogger and Bio 185 Student: Saum Senemar

What is the first thing we think of about coral reefs? Tropical destinations? Snorkeling? Coral reefs are made of millions of cells that are in the phylum cnidaria. How would you think they reproduce and grow? Well recently a study was done and researchers found out that when coral are in the larvae stage they follow sound and swim toward the stimulus and end up growing there. According to the scientists who did the research the coral larvae have tiny little hairs on their bodies that react to stimuli such as sound waves and swim toward them. The sounds that the coral most likely hear are the slurping sounds of fish or whenever fish scrape coral reefs. This is a perfect example of an adaptive trait because without this ability to swim toward the sound the coral wouldn’t be able to reproduce. The fact that these little cells can respond to sound  is just mind-blowing! Never in a million years would I come to the conclusion that these guys just hear sound and swim toward it. From afar a coral reef looks pretty dormant in activity when in reality probably millions of cells are lurking around responding to sound. Scientists also did tests to confirm this phenomenon by placing speakers underwater and waiting to see what happened. The coral actually grew upward toward the speakers. The scientists are also looking at potential hazards to the coral like human interactions in the form of boats and what not because they say that the coral reefs are dying. Also sonar and wind turbines can be a huge problem. Whales for example get a lot of nutrition from the coral reef and they could be impacted in result of the coral reef dying. Coral reefs are very fragile because they really don’t have any protective feature. This is definitely not a good thing because the coral reef is the base of nutrition for many important organisms and animals. And whats also worth knowing is that many other organisms may act the same way by reacting to sound according to the same scientists who conducted the study. Read more about the original story here:  http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0010660

Many coral reefs worldwide have been dying, and one researcher pointed out that human activity in the ocean could be making enough noise to interfere with the baby coral’s ability to find safe places to settle. (Wolf Hilbertz, Associated Press / May 20, 2010: http://www.latimes.com/news/science)

Before we get serious, I’d like to see the results of your genetic testing kit
May 23, 2010, 5:42 pm
Filed under: Human biology, Student post

by Guest Blogger and Bio 185 Student: Pauline Do

Imagine a world of dating where you could ask your significant other for the genetic risks he or she carries before you decided to start a family with this person. High blood pressure? Strong likelihood of getting a heart attack? Sayonara. Well, look no further and imagine no more because  San Diego-based company Pathway Genomics plans to make genetic testing kits called the Insight test available at 6,000 Walgreens stores nationwide. Although genetic testing kits are old news, this decision signals the first attempt at mass marketing personalized genomic medicine.

Ranging from $20-$249 per kit, customers are instructed to spit into a vial which is sent to the company. Depending on the amount of money spent, the company will test  customer’s DNA for 23 genetic conditions that they carry (and can potentially pass on to their children) such as diabetes or 23 conditions they are at risk for such as high blood pressure and obesity. Another test presents likely responses a customer’s body would make if introduced to 10 different substances such as caffeine and an assortment of other drugs.

Opponents of the kit maintain that because few things are understood about reading genetic markers, results from the kit will be inconclusive. Paralleling the Humane Genome Project, there is a possibility of misusing and misinterpreting the information. However, the company argues results could motivate individuals to lead healthier lifestyles and even provides guidance for interpreting results over the phone.

According to Robert Stein, many are also concerned that: “[the kit] will open a Pandora’s box of confusion, privacy violations, genetic discrimination and other issues.” Adding to the confusion, many customers may psych themselves out and procure an unwarranted sense of security which could lead to negligence of important, preventive measures or over-worry about diseases and conditions they don’t have which could lead to uncalled for costly treatments.

In my opinion, these genetic kits are precarious. I agree with the article when it says that our decision to genetically test ourselves could lead to testing of the fetus. I think this leads to parents playing “God”. People could become discriminatory and decide they’d rather have an abortion and try again, to obtain the perfect baby. As kits become more advanced and more companies join the arena of over-the-counter kits, maybe the parents will want blue eyes over brown eyes or maybe they don’t want to deal with the costs of a diabetic child. In the same manner, a person in a serious relationship might decide to end it because, “There is no way I’d want to marry a guy who might have leukemia in the future”. Moreover, what if companies begin to play on these issues to make more money? My belief is that access to such information is controversial and people are unready to deal with such power.

To read more  (or to test  your genes, whatever floats your boat), the article is available at http://www.washingtonpost.com/wpdyn/content/article/2010/05/10/AR2010051004904_2.html?g=0.

Life in the intertidal: no day at the beach!

I spent the past couple of days exploring the intertidal with my biology students. No matter how many times I visit this coastal system, I am always fascinated by how much beauty and how much biology there is to observe. Especially when I go with students whose “oooohs” and “ahhhhhs” remind me once again of how amazing the natural world is.

Here in So Cal, we are lucky to have so much coastline to explore. Crystal Cove State Park in Laguna Beach has 3.2 miles of pristine coastline that is perfect for exploring tidepools and sandy coves, or just relaxing on the beach.

Life in the intertidal is no day at the beach. Organisms need to cope with being exposed to air and sunlight during low tides and submerged with water during high tides. They also have to be able to withstand the incessant pounding of the energy-filled surf and compete with other organisms who are looking for a prime piece of real estate. Animals have evolved suites of adaptations in responses to these environmental challenges. Here are a few of my favorites (oh so hard to just pick a few….more to come in future posts!):

Ochre Sea Stars (Pisaster ochraceus) are common inhabitants on rocky beaches all the way from Baja California to Alaksa. Students are often very excited to find these creatures and remark “Awwww…..how cute!!”. I agree, but quickly remind them what voracious predators these animals are. The ochre sea star is a major predator of mussels, barnacles, limpets and snails. We found this guy here mid-meal: the animal is using its hundred of tiny tube feet to latch on to the shells of this mussell, tugging until they open. The sea star then extrudes its stomach out of its body into the opened shells and digests the mollusk in place. Once it is satisfied with its meal, the stomach is brought back inside the body and the partially digested food is moved to a second stomach (pretty “cute”, huh?).

A few more quickies:

Do not disturb this California Sea Hare (Aplysia californica: a hermaphroditic marine gastropod mollusk); it is capable of squirting you with a reddish-purple ink from a gland in its mantle cavity (much like an octopus does).

These small aggregating sea anemones (Anthopleura elegantissima) are often mistaken for debris covering the rocks. In fact, they are almost always covered with sand and shell pieces, which may conserve moisture, prevent sun damage during exposure, and help in hiding from predators.

Where’s Waldo? Green algae, brown algae, mussels, barnacles, sea stars and more!

Happy St. Patrick’s Day!
March 17, 2010, 10:16 pm
Filed under: Diversity in the plant world

The Shamrock (Trifolium repens)

What is the first think we think of when we think of St. Patrick’s Day? Okay, I mean the second thing we think of….the shamrock! The shamrock is a clover of the variety Trifolium repens. Shamrock’s typically have 3 leaflets and is what St. Patrick used to represent the Holy Trinity. You are all probably familiar with the lucky four-leaf variant which is often confused with the Shamrock. While the four-leaf clover is a symbol of good luck, the three-leafed shamrock is mainly an Irish-Christian symbol.

It has been estimated that there are approximately 10,000 three-leaf clovers for every four-leaf clover, however this probability has not deterred collectors who have reached records as high as 160,000 four-leaf clovers. Clovers can have more than four leaflets: the most ever recorded is twenty-one, a record set in June 2008 by the same man who held the prior record and the current Guinness World Record of eighteen. Unofficial claims of discovery have ranged as high as twenty-seven.

I have come to know this plant very well. As an undergraduate, I studied how differences in leaf traits among clovers is related to their susceptibility to pathogens. Put another way, I once spent 24 hour in a greenhouse watching water evaporate off of clover leaves. Yes, I did. All in the name of Science!

**UPDATE: Don’t be surprised if you see a lot more ” lucky clovers” around:

Plant nurseries in clover after finding four-leaf gene

The science of weddings
March 11, 2010, 5:19 pm
Filed under: Human biology

I am getting married in 16 days. I like to think that i’ve taken a scientists approach to the wedding—I think many brides would covet my many excel spreadsheets. But my approach is nothing compared to that of bride Linda and her groom Nic. They added an unexpected dimension to their nuptials; they decided to conduct an experiment to determine what happens to our bodies when we say “I do”.

Researcher Paul Zak measured levels of oxytocin in the bride, groom, three close family members and eight friends before and after the ceremony (now those are some dedicated bridesmaids!!). Oxytocin is released from the pituitary gland in the brain and has been dubbed the “cuddle chemical” because of its association with bonding, trust, and generosity (it also triggers childbirth and the release of milk during breastfeeding).

As expected, the bride and groom both experienced a surge of the “cuddle” hormone during the ceremony (as did the mother of the bride and father of the groom!). The closer the genetic relatedness to the bride and groom, the higher the level of oxytocin.

Researcher Paul Zak proposes that this “group oxytocin” surge supports the theory that public weddings have evolved as a way of binding couples to their friends and families (perhaps to help out with future child-rearing in order to increase biological fitness!!). It is also not surprising that they observed a greater spike in the hormone in family members than in friends.

To learn about the action of the other hormones measured at their wedding (vasopressin–released during sex, involved in male aggression and pair bonding’ testosterone–released by the testes, levels tend to fall in the early stages of a relationship; ACTH and cortisol–“stress hormones”, moderate levels promote the release of oxytocin but high levels inhibit it), read the New Scientist article at http://www.newscientist.com/article/mg20527471.000-my-big-fat-geek-wedding-tears-joy-and-oxytocin.html?full=true

PS I wouldn’t want blood being drawn an hour before my vows but I am pretty jealous of the centrifuge in the bridal ready room

Can I borrow your spines please?
March 10, 2010, 4:42 pm
Filed under: Diversity in the animal world

This Urchin Crab (Dorippe frasconce) is carrying a fire urchin on its back (Astropyga radiata). Now why in the world would it want to do that?? The crab is taking advantage of the long sharp spines the urchin has to protect it from predators. Why grow your own spines when you can borrow someone elses?

Is it a plant or is it a slug??

Elysia chlorotica, a photosynthesizing slug!

You might be surprised to learn that the ability to make sugar from sunlight and carbon dioxide is not something that only plants can do! In fact, the ability to do photosynthesis evolved in Bacteria.

And now there is evidence that some animals have taken advantage of this lifestyle. Researchers have found that the sea slug, Elysia chlorotica, can photosynthesize! If you shine light on one of these guys, they convert carbon dioxide into sugar and make oxygen just like a plant!

If you are one of my students, hopefully you are thinking, “Wait one second!! Animals lack chloroplasts (as do bacteria by the way!), HOW in the world could an animal be photosynthesizing?!”

Well, the answer to that question is quite and interesting one. These slugs are about 3 cm long and look quite leaf-like. They are found off the east coast of North America, ranging from Florida to Nova Scotia. Basically, the sea slug eats the tiny algal cells and incorporates their chloroplasts into their own cells. The sea slugs have special cells that the line their digestive tubules that are capable of taking up the chloroplasts from the algae. Even crazier is that the chloroplasts can live inside the slugs’ cells for 9 – 10 months!! This is about the entire lifetime of the slug and can provide the slug with essentially all the energy it needs!

Still interested?? Another neat aspect of this story is the fact that chloroplasts themselves are not enough to do photosynthesis. The process also requires certain enzymes and proteins to keep the chloroplasts working. Researchers have shown that at some point in the evolution of these slugs genes from the algae were transferred over and now reside in the genome of the slug! Gene transfers are extremely common among single-celled organisms, but this is the first time it’s been described in multicellular organisms!! How did they get there?? The answer to that question could lead to major strides in gene therapy and genetic engineering.

This research was presented at annual meeting of the Society for Integrative and Comparative Biology in Jan 2010 and has yet to be published. Check out Dr. Sidney Pierce’s website for more information on this research: http://biology.usf.edu/ib/faculty/spierce

Welcome to “Biophilia”
March 5, 2010, 6:27 pm
Filed under: Human biology

The term “biophilia” was coined by Edward O. Wilson, a Harvard University entomologist, naturalist, and conservationist. I have had a fondness of E.O. Wilson ever since he declared that if he could start his life over he would work in microbial ecology! Back to biophilia—Wilson introduced the term to describe the instinctive bond between human beings and living systems. Literally, biophilia means “love of life or living systems“. It can be thought of as the “innate tendency to focus on life and lifelike processes” or the “connection that human beings subconsciously seek with the rest of life”.

So that is the inspiration for this blog….to share my love of life and living organisms and living systems with my friends, family, and students. I hope to highlight for you some of the wonders and marvels of the natural world.  In E.O. Wilson’s words, “If you study life deeply, its profundity will seize you suddenly with dizziness . . .”