=== A Saturday with the Sea Turtles ===
Hawaii's green sea turtle, has been classified as an endangered species for over 25 years. Signs around the Mauna Lani lagoon warn tourists to keep their distance from the humped creatures that look like gray-green boulders along the shoreline. My friends and me, however, ignore the signs, wade into the water, and struggling to flip a 150-pound turtle onto its back in the center of an oversized inner tube. We aren't being intentionally cruel. Nor are we breaking the law. We are spending another sunny Hawaiian Saturday volunteering for a government-sponsored sea turtle research project. We float our latest turtle ashore. Flippers flapping and beak snapping, the turtle resists as we hoist it onto the examination table that we've set up beneath an awning on the beach. It's my turn to enact the exam. As I weigh the turtle and measure its carapace (shell), another volunteer, Kiko, watches as I record the data. Tourists always seem delighted by the opportunity to closely observe a turtle. Kiko tells the tourists that this turtle has likely made a remarkable migration from breeding grounds in shoals located over 400 miles away. I open the turtle's mouth so I can document what it has been eating, and I wonder if the turtle is hungry. Kiko laughs and says that one of the first lessons a volunteer learns is that green sea turtles have terrible breath! A supervising marine biologist helps me insert a small microchip-a tag-beneath the skin of one flipper. Tagging helps with monitoring the turtle population and gathering information to help the turtles recover from their endangered status. After we pull the heavy turtle back to the water. I don fins, a mask, and a snorkel watching the turtle after it's released. Though shy and quiet on land, these animals are graceful swimmers. Kicking my fins, I follow the turtle as it beats its flippers like wings and soars through the canyon reefs toward the deep water beyond.
=== ... ===
rants, ethnic minorities, women, and children. In 1965, she became the first Asian American woman to be elected to the U.S. Congress when she won the first of six consecutive elections. For example, in addition to Title IX, Mink introduced: the Early Childhood Education Act and supported the Women's Educational Equity Act. All three were landmark laws because they substantially altered civil rights policies.
=== Playing the Theremin ===
The theremin, the first electronic musical instrument, invented in 1918 by Russian physicist, Leon Theremin. Its eerie, high-pitched sound has been compared to that of stringed instruments-particularly the violin-and even to a wailing human voice. Not in widespread use today, a major film featured the theremin is perhaps best known for its use in sound tracks of 1950s science fiction movies, such as The Day the Earth Stood Still.
=== Radiocarbon Dating, Tree Rings, and the Distant Past ===
Radiocarbon dating, developed by Willard F. Libby in the 1940s, seemed to offer archaeologists a definitive method for determining the age of artifacts. The method for archaeologists to date artifacts was based on the amount of radioactive carbon 14 found in organic matter such as wood, bones, and shells.
=== ... ===
established theories archaeologists had developed on the basis of Egyptian dynastic records.