Male larval experience of cues from adult rivals alters lifetime sperm investment patterns in a sperm heteromorphic moth, Ephestia kuehniella

Using a sperm heteromorphic moth,Ephestia kuehniella, we investigate how male larvae of different ages respond to cues from adult rivals and adjust their lifetime sperm production and ejaculation. We demonstrate that in response to adult male cues, late instar larvae produce more sperm before emergence and their resultant adults have shorter mating latency and ejaculate more sperm in the first few matings. If juveniles produce more fertile eupyrene sperm before emergence, their adults stop making these sperm, but regardless of the number of infertile apyrene sperm produced during the juvenile stage, adults continue to make them. AbstractMale animals may adjust their resource allocations for reproduction and other fitness functions in response to cues from rivals. For instance, adult males increase their investment in sperm for a higher paternity share when they perceive sperm competition risk in their surroundings. In nature, both juveniles and adults may coexist spatially and temporally. Yet, it is not clear how juvenile males of different ages respond to cues from adult rivals and fine-tune their lifetime investment in sperm production and ejaculation in any insect. Here we used the Mediterranean flour moth,Ephestia kuehniella, which produces both fertile eupyrene and infertile apyrene sperm, to explore this question. We demonstrate that the late, but not early, instar larvae are sensitive to adult male cues. As a response, they produce more sperm before emergence and their...

Source: Insect Science - May 10, 2023 Category: Biology Authors: Junyan Liu, Xiong Zhao He, Qiao Wang Tags: ORIGINAL ARTICLE Source Type: research