Fossils can be used to match up rock layers. As organisms change over time, they look different. Older fossils will look different than younger fossils. Some organisms only survived for a short time before going extinct. Knowing what organisms looked like at certain times also helps date rock layers. Some fossils are better than others for this use. The fossils that are very distinct at certain times of Earths history are called index fossils. Index fossils are commonly used to match rock layers. You can see how this works in Figure 2.30. If two rock layers have the same index fossils, then they're probably about the same age.

How are index fossils useful?

The violent arena of domestic abuse litigation has grown a bit more volatile here, now that a judge has decided to hold two women in contempt of court for returning to men who had been ordered to stay away from them. "You can't have it both ways," said Judge Megan Lake Thornton of Fayette County District Court in recently fining two women $100 and $200 respectively for obtaining protective orders forbidding their partners from contacting them, then relenting and contacting the men. Ruling that the order was mutually binding, Judge Thornton also cited the men for contempt. "It drives me nuts when people just decide to do whatever they want," said Judge Thornton, who is experienced in the state's thick domestic abuse docket, which produces close to 30,000 emergency protective orders a year. Kentucky officials say there is a virtual epidemic of abusive relationships in the state. Judge Thornton's ruling has alarmed advocates for battered women, who plan to appeal it. The advocates say the finding goes beyond existing law and is unrealistic because some renewed contacts often prove unavoidable in domestic abuse cases, which involve economic and family dependency and other complications of daily living. The state office on domestic violence has pointedly agreed, warning that the ruling could cause abused women to hesitate in bringing their plight before the courts for fear of being chastised for their trouble. "The reality is it's easy to say they should never have contact," said Sherry Currens, executive director of the Kentucky Domestic Violence Association, an advocacy and legal protection group. "But we're talking about people in long-term relationships. They may have children in common. It's pretty hard to say, 'Never speak again.' People have financial difficulties. They may love the partner. It's not an easy thing." But Judge Thornton declared in court, "When these orders are entered, you don't just do whatever you damn well please and ignore them." The ruling stunned Cindra Walker, the lawyer for the two women, who is with Central Kentucky Legal Services, which represents many of the thousands of indigent women caught in abusive relationships. "For over five years, I've been in court practically every day on these abuse cases," Ms. Walker said, "and I've never before had a victim threatened with contempt."

What prompted Judge Megan Lake Thornton to make the statement: "You can't have it both ways."

You couldnt survive without your skin. It has many important functions. The main function of the skin is controlling what enters and leaves the body. It prevents the loss of too much water from the body. It also prevents bacteria and other microorganisms from entering the body. The skin helps maintain a constant body temperature. It keeps the body cool in two ways. Sweat from sweat glands in the skin evaporates to cool the body. Blood vessels in the skin dilate, or widen. This action increases blood flow to the body surface. This allows more heat to reach the surface. The heat is then able to radiate off the body. The opposite happens to retain body heat. Blood vessels in the skin constrict, or narrow. This decreases blood flow to the body surface. This reduces the amount of heat that reaches the surface. When this happens, less heat can be lost to the air.
What happens when less heat reaches the surface of your skin?