Monday, February 2, 2009
Are humans vegetarians or omnivores?
Thomas M. Greiner, Assistant Professor of Anatomy / Physical Anthropology
Those terms are not strict biological designations, and so the question
needs to be rephrased a bit before it can be answered. The confusion stems
from the use of the word "carnivore" to mean "meat eater" - instead the
word carnivorous should be used. To be biologically strict here, a
carnivore is an order of mammal (recognized by the presence of the
carnassial tooth, among other things) that includes cats (felids), dogs
(canids), bears (ursids), and a number of other mammalian families.
Carnivores are not strictly meat eaters - most will eat some type of plants
as a part (sometimes even the main part) of their diet.
The term "vegetarian" is strictly a human construct. Vegetarians shun
animal products for food, usually for religious or ethical reasons. Even
still, there are degrees of vegetarian. Some vegetarians will never
consciously eat any food that comes from an animal. Other will consume
dairy products (an animal food even though it isn't meat). Others will
allow themselves to eat eggs (the pre-chicken, so to speak), or fish.
Vegetarianism is more of a dietary philosophy then an ecological food
preference, so it's hard to speak of it in biological terms.
Biologists rarely (never in my experience) categorize non-carnivorous
animals into one "plant eating" group. That is because different dietary
specializations are required to eat different types of plants. Thus, you
will hear of herbivores (specialized to eat shoots and growing tips),
folivores (specialized to eat leaves) and frugivores (specialized to eat
fruit) among other adaptations. Even within these broad groupings there are
further specializations, such as grazers that eat grass and browsers that
eat shrubs (both are types of herbivore). And even among the "plant eating"
animals there is no animal that I am aware of that will not consume some
type of animal protein when given the opportunity.
An omnivore is an animal that will draw its food from all aspects of the
ecosystem (plants, animals - whatever). As I've already pointed out, you
could claim that nearly every animal is omnivorous since a purely meat
eater or purely plant eater is very rare. Nonetheless, you can look at the
animal's anatomy to look at how they are adapted to process food.
First you can look at the teeth.
Molars are broad flat teeth that are useful in grinding up tough fibrous
material - such as plants. Animals that are primarily plant eaters have
very large molars with six pairs (three uppers and three lowers) on each
side. Animals that do not specialize in eating plants tend to have a
reduced number of molars. Humans are equipped with six pairs of molars.
Although they are not very large, this would suggest that humans have the
ability to process fibrous plant food.
Premolars (bicuspids) are the slicing teeth. Mammals originally had eight
pairs of premolars, although most mammals alive today have fewer. Premolars
are the primary teeth used by meat eating specialists, and are frequently
missing in animals that specialize in plant foods. Humans have four pairs
of premolars, which suggests that humans have the ability to process animal
food.
Incisors are grasping teeth, that change shape depending upon how they are
used. The broad flat surfaces of human incisors is most associated with
animals that specialize in eating fruit.
So, if we just look at our teeth - humans are clearly built to be
omnivorous. But, of course there is more data. We can look at how nutrients
are processes and absorbed in the body.
Meat and fruit are high quality foods that are not difficult to assimilate.
Animals that specialize in these types of food tend to have a short
digestive tract, with a very short large intestine. Plant foods can be
nutritious, but take longer to absorb. Therefore, animals that specialize
in plant eating tend to have long and elaborate digestive tracts. Humans
are clearly intermediate here. We have a long large intestine (more common
in plant eaters), but we lack the elaborations that would allow us to
digest and assimilate nutrients from high fiber plant foods (such as
grass or leaves). So, again, the human digestive tract can be used to argue
that we are omnivorous.
Finally, you need to look at nutritional requirements. There are some
B-complex vitamins that are available only by eating other animals. The
human body requires this nutrient, but does not synthesize it the way some
other animals do. Therefore, if humans truly ate no animal foods, and had
no artificial vitamin supplements, they would sicken and die. In nature,
there are no true "human vegetarians."
Humans are omnivores. The order of mammals that includes humans (the
primates) are all omnivores. To be sure, the modern American diet includes
a lot more meat than is healthy. And the human animal can be very healthy
by being a lot more vegetarian. But to never eat meat is both unnatural and
unhealthy.
Finally, you ask about my credentials to answer this question. Well, I am
employed as an anatomy professor (and am therefore a specialist in human
anatomy). I teach at a college that specializes in training health care
workers (so I am familiar with issues of human health an nutrition).
Finally, I earned by Ph.D. in Physical Anthropology (which sort of makes me
an expert in how humans adapt both biologically and culturally to the
environment).
Some References relevant to this questions:
Harding, RSO & Teleki, G (1981) Omnivorous Primates. Columbia University
Press: New York.
Romer, AS & Parsons, TS (1986) The Vertebrate Body. Saunders College
Publishing: New York
Oxnard, C. (1987) Fossils, Teeth and Sex. University of Washington Press:
Seattle
Sunday, February 1, 2009
Vegetarian...
Saturday, January 31, 2009
Octuplets' mum already has six children
AN ethical debate erupted Friday after it was learned that the Southern California woman who gave birth to octuplets this week had six children already.
Large multiple births "are presented on TV shows as a 'Brady Bunch' moment. They're not," fumed Arthur Caplan, bioethics chairman at the University of Pennsylvania. He noted the serious and sometimes lethal complications and crushing medical costs that often come with high-multiple births.
But Dr. Jeffrey Steinberg, who has fertility clinics in Los Angeles, Las Vegas and New York, countered: "Who am I to say that six is the limit? There are people who like to have big families."
Kaiser Permanente announced the mega-delivery Monday, with delighted doctors saying they had initially expected seven babies and were surprised when the cesarean section yielded an eighth.
Multiple births this big are considered impossible without fertility treatment, but the doctors who delivered the babies would not say whether the 33-year-old woman had used fertility drugs or had embryos implanted in her womb.
However, the children's grandmother, Angela Suleman, was quoted as telling the Los Angeles Times that her daughter had embryos implanted last year, and never intended to give birth to eight, but "they all happened to take." Suleman said her daughter rejected an offer from doctors to abort some of the embryos.
More common among younger women is the use of fertility drugs that stimulate egg production; doctors are supposed to monitor budding eggs and stop the drugs if too many develop.
Some medical experts were disturbed to hear that the woman was offered fertility treatment, and troubled by the possibility that she was implanted with so many embryos.
Dr. David Adamson, former president of the American Society of Reproductive Medicine, said he was bracing for some backlash against his specialty.
In 30 years of practice, "I have never provided fertility treatment to a woman with six children," or ever heard of a similar case, said Adamson, director of Fertility Physicians of Northern California.
Women seeking fertility treatment are routinely asked to give a detailed history of prior pregnancies and births, and "it's a very realistic question to ask about someone who has six children: How does this fit into the concept of requiring fertility treatment?" Adamson said.
The woman's fertility doctor has not been identified. The hospital has not released the mother's name, citing her desire for privacy. There was no immediate information on whether she is married or who the father of the babies is. Her six other children range in age from 2 to 7.
Records show that she held a psychiatric technician's license from 1997 to 2002. It was unclear whether she is now employed.
It was only the second time in U.S. history that eight babies survived more than a few hours after birth. The six boys and two girls were said to be in remarkably good condition but were expected to remain in the hospital for several more weeks.
The mother of the octuplets lives with her parents in a modest, single-story home on a quiet cul-de-sac in Whittier, a Los Angeles suburb of about 85,000. Children's bicycles, a pink car and a wagon were scattered in the yard and driveway.
On Thursday night, the children's grandfather came to the door and angrily told reporters to leave the property.
Court records show Angela Suleman filed for bankruptcy last March, but after she failed to make required payments and appear at a creditors' meeting, the case was dismissed. She reported liabilities of $981,371, mostly money owed on two houses she owns in Whittier.
The births were a hot topic of conversation on the Internet, with many people incredulous that a woman with six children would try to have more — and that a doctor would help her do so. Some criticized the doctor and suggested that the mother would be overwhelmed trying to raise her brood and would end up relying on public support.
Jessica Zepeda, who identified herself as a friend of the mother, said the woman and family would have enough money to raise 14 children. "She is not on welfare," Zepeda said. "She is an awesome mom, and will be able to take care of her babies."
Several doctors said it is not their role to dictate family size.
"I am not a policeman for reproduction in the United States. My role is to educate patients," said Dr. James Grifo, professor of obstetrics and gynecology at the New York University School of Medicine.
But Caplan said not enough attention is paid to the well-being of the children in high-multiple births. Such babies are often premature and underdeveloped, and are almost always found to have some health problem.
Caplan said everyone has a stake in mega-multiple births because they cause insurance premiums to rise when hospitals cannot get reimbursed for the huge costs such babies incur, and because those with disabilities typically require social services.
"To say all you need is cash and the will to have more kids should not be a sufficient standard to access services," he said. "It is insufficient for adoption. It isn't sufficient to be a foster parent. Why would it be sufficient to run down to the fertility clinic to get embryos transplanted or super-ovulated?"
A few years ago, Caplan and others did a survey of U.S. fertility clinics. They found few had policies for deciding whether to help a woman get pregnant. Most clinics said they had patients meet with financial coordinators, but only 18 percent had them see a social worker or psychologist.
With in vitro fertilization, doctors frequently implant more than one embryo to improve the odds that one will take. Mothers-to-be who are found to be pregnant with several babies are given the option of aborting some of them to increase the chances the others will survive.
The U.S. fertility industry has guidelines on how many embryos doctors can implant, with the number varying by age and other factors. The guidelines call for no more than one or two for a generally healthy woman under 35, and no more than three to five, depending on the embryos' maturity, for women over 40.
If eight embryos were implanted at once, that is "well beyond our guidelines," Dr. R. Dale McClure, president of the reproductive medicine society, said in a statement.
Clinics that clearly violate guidelines can be kicked out of another group, the Society for Assisted Reproductive Technology, which in turn affects whether insurance covers their services. But the guidelines do not have the force of law.
Article from: 
Waltz with Bashir.
Fresh movie, winner of the Golden globe for "Best foreign film" and nominated for oscars as well, u gotta check this one out, very artsy and powerful.
Slavery...
Everywhere I saw slavery being carried in processions toward the alters and being called "GOD".
They poured libations of wine and perfume at its feet and called it "ANGEL".
They burned incense before its image and called it "PROPHET".
They fell down prostrate before it and call it "THE HOLY LAW".
They fought and killed for it and called it "PATRIOTISM".
They submitted to its will and called it "THE SHADOW OF GOD ON EARTH"
They burned their houses and razed their buildings at its will and called it "FRATERNITY and EQUALITY".
They strove then and made every effort for it, calling it "WEALTH and TRADE".
Indeed, it has many names and but one reality, many manifestations of a single substance. it is a single disease, eternal without beginning, without end,appearing with many contradictory symptoms and differing sores, inherited from the fathers by the sons as they inherit the breath of life. The ages receive its seeds in the soil of the ages, just as the seasons reap what the seasons have sown.
Hunchbacked slavery, slavery that makes a people subject to the laws of other people.
Mangy slavery, slavery by which the sons of kings are crowned kings.
Dark slavery, slavery by which the innocent children of criminals are branded with shame.
Slavery to slavery itself, the power by which it continues.
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