Problem: I read this background article the other day: New species develop naturally through the process of natural selection . Due to natural selection, organisms with traits that better enable them to adapt to their environment will tend to survive and reproduce in greater numbers. Natural selection causes beneficial heritable traits to become more common in a population and unfavorable heritable traits to become less common. For example, a giraffe’s neck is beneficial because it allows the giraffe to reach leaves high in trees. Natural selection caused this beneficial trait to become more common than short necks.  I am facing a new situation today: There is a creature called a Brotor that has inhabited the planet Glarknon for thousands of years. The Brotor have two distinct traits on them, but each Brotor only has one of these traits. The vast majority of Brotors have fins on their body, but there is a very small segment of the Broto population that has arms instead of fins.  Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which trait is more suited for the Brotor's environment?

A: fins


Problem: I read this background article the other day: Lactose intolerance is due to the lack of enzyme lactase in the small intestines to break lactose down into glucose and galactose.[3] There are four types: primary, secondary, developmental, and congenital.[1] Primary lactose intolerance occurs as the amount of lactase declines as people age.[1] Secondary lactose intolerance is due to injury to the small intestine such as from infection, celiac disease, inflammatory bowel disease, or other diseases.[1][4] Developmental lactose intolerance may occur in premature babies and usually improves over a short period of time.[1] Congenital lactose intolerance is an extremely rare genetic disorder in which little or no lactase is made from birth.[1]  I am facing a new situation today: David works for a large pharmaceutical company as a research scientist. He has devised a procedure which can detect lactose intolerance in patients easily. To test his procedure he picked up four subjects form a large pool of sample. The four subjects are subject A, subject B, subject C, and subject D. Subject A has primary lactose intolerance; subject B has secondary lactose intolerance; subject C has developmental lactose intolerance; and subject D has congenital lactose intolerance.  Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Would subject A be younger or older than subject C?

A: older


Problem: I read this background article the other day: HIV , or human immunodeficiency virus, causes AIDS. AIDS stands for "acquired immune deficiency syndrome." It is a condition that causes death and does not have a known cure. AIDS usually develops 10 to 15 years after a person is first infected with HIV. The development of AIDS can be delayed with proper medicines. The delay can be well over 20 years with the right medicines. Today, individuals who acquire HIV after 50 years of age can expect to reach an average human life span.  I am facing a new situation today: Two college students both had unprotected sex with different partners. Ben got the HIV virus, while Nate was lucky and was not infected with any diseases.  Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which student had a greater chance of reaching an average human life span?

A: Nate


Problem: I read this background article the other day: Some of Antarctica has been warming up; particularly strong warming has been noted on the Antarctic Peninsula. A study by Eric Steig published in 2009 noted for the first time that the continent-wide average surface temperature trend of Antarctica is slightly positive at >0.05 °C (0.09 °F) per decade from 1957 to 2006. This study also noted that West Antarctica has warmed by more than 0.1 °C (0.2 °F) per decade in the last 50 years, and this warming is strongest in winter and spring. This is partly offset by autumn cooling in East Antarctica. There is evidence from one study that Antarctica is warming as a result of human carbon dioxide emissions, but this remains ambiguous. The amount of surface warming in West Antarctica, while large, has not led to appreciable melting at the surface, and is not directly affecting the West Antarctic Ice Sheet's contribution to sea level. Instead the recent increases in glacier outflow are believed to be due to an inflow of warm water from the deep ocean, just off the continental shelf. The net contribution to sea level from the Antarctic Peninsula is more likely to be a direct result of the much greater atmospheric warming there.In 2002 the Antarctic Peninsula's Larsen-B ice shelf collapsed. Between 28 February and 8 March 2008, about 570 km2 (220 sq mi) of ice from the Wilkins Ice Shelf on the southwest part of the peninsula collapsed, putting the remaining 15,000 km2 (5,800 sq mi) of the ice shelf at risk. The ice was being held back by a "thread" of ice about 6 km (4 mi) wide, prior to its collapse on 5 April 2009. According to NASA, the most widespread Antarctic surface melting of the past 30 years occurred in 2005, when an area of ice comparable in size to California briefly melted and refroze; this may have resulted from temperatures rising to as high as 5 °C (41 °F).A study published in Nature Geoscience in 2013 (online in December 2012) identified central West Antarctica as one of the fastest-warming regions on Earth. The researchers present a complete temperature...  I am facing a new situation today: Frank and Noah were two researchers. Noah researched the climate of Antarctica, while Frank researched the climate changes of Madagascar and the Southern tip of Africa.  Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which researcher observed a large amount of surface warming?

A:
Noah