Sexual selection emphasises the development of characteristics that demonstrate in a way that cannot be faked just how fit that characteristic's possessor is to father (or mother) another individual's offspring.

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"Previous experiments have indicated that when you select for a reduction in aggressiveness, you obviously get a tamer animal but you also get an animal that retains juvenile characteristics much longer during development, sometimes into adulthood, " said Dr Axelsson.

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Without clarity about core customer characteristics, entrepreneurs will rely on ad hoc approaches to evaluate business development opportunities.

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"We are collecting in-service aircraft components to asses the remaining characteristics and capability in terms of stress and fatigue, " says Olivier Malavallon, project director of business development and change at Airbus.

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