Larry MacPhee: Biology


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DIY Biology Labs and Lessons

I've been gathering a collection of great activities, links, notes, and lessons for teaching Biology. Visit my resource page for a look. My emphasis is on free materials appropriate to the high school AP Bio and university Intro Bio audiences.


Below you will find a collection of blog articles I write as I come across interesting stories about evolutionary biology and the nature of scientific inquiry. I hope you'll find them interesting.

The Chimera

The Chimera of Greek Mythology is a fire-breathing female monster with a lion's head, a goat's body, and a serpent's tail. A genetic chimera, in contrast, is a single organism composed of cells with more than one distinct genotype. How does this happen, and what are the ramifications? In agriculture, chimeras are common. Most of our fruit trees, for example, have a desirable fruit bearing variety, that may be somewhat fragile, grafted to the root stock of a hardier plant, giving it greater resistance to disease and pests. In plants, this is as simple as notching the two plants' branches and taping up the joint until they grow together. Plants are surprisingly tolerant of this. Chimeras also occur naturally however, and even in the higher vertebrates, where you might think that tissue rejection would put a stop to such things. One human chimera was discovered when a professional athlete offered up a cheek swab to satisfy the gender tests required by the Olympic committee. In this case the person, who physically appeared female, came up as male. The eventual explanation of this puzzle was that, in utero, the woman had partially absorbed her unborn fraternal twin, but that the two genotypes managed to coexist in a single body. Another case was discovered when it was learned that a woman who was suffering from a life threatening cancer was able to beat it back thanks to the assistance of a fetus she had aborted years earlier, but who's genes had crept across the placental barrier and integrated into her tissues. It may be the case that women are more tolerant of these chimeric conditions because the placenta is not a perfect barrier, and that they have developed a tolerance for it, in order to survive. This strange condition may be more common than we realize, and may prove to be a promising line of research that could greatly increase the success rates of organ transplant.

Revolutionary Thinking

Teach the Controversy?!

The Meaning of Life

The Problem of Perfection

Survival Machines

The Obesity Epidemic

Crime and Punishment

Our Prosthetic Future

Does Free Will Exist?

Life In the Universe

Getting Sick


Mitochondrial Eve

The Domestication of Dogs

Restoring a Fishery

Living at Elevation

A Cure for the Common Cold

Survival of ...the Cutest? ...the Spiciest?

Why can't we eradicate the diseases for which we have vaccines?

Herd Immunity


Living in Space

Fighting Cancer

Parent-Offspring Conflict

What to do with teens? A modest proposal!

Lactose Intolerance

Political Systems

Modern Ailments: Part I

Modern Ailments: Part II

Hidden Causes of Disease

Male Promiscuity


Diet and Exercise

Longevity: Part I

Longevity: Part II

Longevity: Part III

Other Topics

We hold these truths to be self evident...

Why Darwin is still controversial

Anti-Science Backlash

Science as a "Way of Knowing"

The Scientific Creed

Science and the Law

Science and the Press

Science and the Charlatans

Science and the Nature of Discovery

Science and the Silver Screen

Correlation vs. Causation

Limitations of Scientific Inquiry

Occam's Razor

Control and Treatment

The Double Blind

The Placebo Effect

Type I and Type II

Precision and Accuracy