Among animals, the fast-slow continuum is the dominant axis that shapes life-history variation.As resources are limited a trade-off occurs between a short lifespan, young age at maturity, high reproductive rates and high aging rates or the other way round. At an ultimate level, rates of adult mortality with age are assumed to determine whether a species falls in the one or in the other continuum, at which high rates of extrinsic mortality select for fast life-histories. Within terrestrial vertebrates (tetrapods), the current record holder for short lifespan is the Labord's chameleon, Furcifer labordi. These chameleons, inhabiting the seasonal western and southwestern deciduous dry forests of Madagascar, were found to have a post-hatching lifespan of only several months. At the onset of the active respectively rainy season, in November, a cohort of hatchlings emerges. Their early life is determined by rapid growth, resulting in fast sexual maturity and subsequent reproduction in January-February. After the mating season, senescent declines become apparent, and at the beginning of the dry season, a fast die-off has been observed in both sexes. Hereafter, the population only exists as eggs, probably as an adaption to survive the harsh dry season. High adult mortality combined with relatively high juvenile (here egg) survival might have ultimately selected for this annual life-history. It is unique in tetrapods and makes this chameleon an intriguing model species for investigating the proximate and ultimate factors shaping rapid senescence, especially because perennial, sympatric congeners are available for comparative studies. Semelparity, i.e. the strategy to allocate all energy in one reproduction event, is rarely found in tetrapods and has apart from a very few reptile species only been detected in a few small-sized marsupial species. However, in these marsupial species the die-off following the mating season is restricted to males, while several females survive until the next breeding season. Apart from these species, for which the male die-off is obligate, less extreme cases of semelparity have been documented. Here, facultative male die-off is restricted to some populations and/or only observed in some years and has been linked to variable resource availability. Strong prey seasonality that leads to a short breeding season has been suggested to explain male semelparity in marsupials, at which high levels of sperm competition combined with female reproductive synchrony select for obligate semelparity. Interestingly, males that were captured before engaging in reproductive season, can survive for more than two years. However, while captivity may shield males from early death due to extrinsic factors, they still experience loss in body mass and irreversible regression of sexual organs as observed in their wild conspecifics after the mating season, proposing an annual, intrinsic pacesetter. In contrast