Whatever that is, it's scary.After 9,000 years of thriving in the absence of mammalian predators, tammar wallabies still startle startle /star·tle/ (stahr´tl) 1. to make a quick involuntary movement as in alarm, surprise, or fright. 2. to become alarmed, surprised, or frightened. at some signs of dangerous mammals, according to according to prep. 1. As stated or indicated by; on the authority of: according to historians. 2. In keeping with: according to instructions. 3. an Australian study. No mammal has threatened the wallabies Macropus eugenii on the unsettled part of Kangaroo Island Kangaroo Island, small island, South Australia, S Australia, at the entrance to Gulf St. Vincent. It is 90 mi (145 km) long and 34 mi (55 km) wide. The chief products are barley, sheep, salt, gypsum, and eucalyptus oil. since the island separated from the Australian mainland. The scientists presented caged wallabies with sights and sounds that might signal unfamiliar but dangerous predators. The sight of a taxidermist-prepared fox stopped the wallabies from foraging and sent them into a frenzy of thumping their hind feet and peering around. The sight of a similarly stuffed cat likewise interrupted dinner and provoked vigilance, report Daniel T. Blumstein and Christopher S. Evans of Macquarie University Location University publications and material indicate that its campus is located in the suburb of North Ryde, although the Geographical Names Board of NSW indicates it is located in the suburb of Macquarie Park. The University has its own postcode: 2109. in Sydney and their coauthors in the September BEHAVIORAL ECOLOGY Behavioral ecology The branch of ecology that focuses on the evolutionary causes of variation in behavior among populations and species. Thus it is concerned with the adaptiveness of behavior, the ultimate questions of why animals behave as they do, rather . In contrast to the sight of a potential predator, recordings of dingoes howling didn't evoke much reaction, especially when compared with the calls of a familiar danger, the wedge-tailed eagle. The wallaby wallaby: see kangaroo. wallaby Any of about 25 species of medium-sized kangaroos, found chiefly in Australia. Brush wallabies (11 species) are built like the big kangaroos but differ in dentition. Rock wallabies live among rocks, usually near water. experiments suggest that wariness about things that look like mammalian predators has endured, while concern about their sounds has faded, Blumstein and his colleagues propose. They say that the wallaby reactions demonstrate an evolutionary quirk called relaxed selection. When changing circumstances reduce the pressure for an animal to maintain some adaptations, such as wariness around predators, those adaptations linger for generations and then fade away in parts (SN: 10/9/99, p. 237). |
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