Evolution of cetaceans decreasing. Other historical climate events can be correlated and matched with the genome history of the Yangtze River dolphin as well. This shows how global and local climate change can drastically affect a genome, leading to changes in fitness, survival, and evolution of a species. The European population of common dolphins ("Delphinus delphis") in the Mediterranean have differentiated into two types: eastern and western. According to a 2012 study, this seems to be due to a recent bottleneck as well, which drastically decreased the size of the eastern Mediterranean population. Also, the lack of population structure between the western and
Creature Features periodically, but never with great success. It was re-broadcast in 1979–1980, but cut due to poor ratings again. "Creature Double Features" was the name of a show broadcast by WKBG Channel 56 in the Greater Boston area. In 1972 WKBG, a station in the Kaiser Broadcasting chain, aired its collection of "Godzilla" movies on Saturday under the title, "The 4 O'Clock Movie". Shortly thereafter, they started calling it "Creature Feature" and then "Creature Double Feature". The show quickly became a staple of the station's Saturday programming schedule during the 1970s and early 1980s. The final show was sometime in 1983.