Cetacea Cetacea Cetacea () is a widely distributed and diverse clade of aquatic mammals that today consists of whales, dolphins, and porpoises. Cetaceans are carnivorous and finned. Most species live in the sea, some in rivers. The name is derived from the Latin "cetus" "whale", itself from the Greek κῆτος "kētos" "huge fish". There are around 89 extant species, which are divided into two groups or parvorders, the Odontoceti or toothed whales, a group of more than 70 species that includes the dolphins, porpoises, belugas, narwhals, sperm and beaked whales, and the Mysticeti or baleen whales, of which there are now
Divided visual field paradigm a lateralized stimulus can be as fast as 150ms following stimulus onset, the lateralized stimulus should only be presented for a duration of 180ms at most. A free software tool called the "Lateralizer" has been developed for piloting and conducting customizable experiments using the divided visual field paradigm. A significant difference between RVF/LH and LVF/RH task performance using the divided visual field paradigm does provide evidence of a functional asymmetry between the two cerebral hemispheres. However, as described by Ivry and Robertson (1998), there are limitations to the types of inferences that can be made from this technique: Visual information