My first meeting of our Society was in 1978. As a PhD student, I had been wondering how the reproductive system responds to changes in the environment. Over the subsequent 40 years, I studied a variety of ‘models’, including ratites, canids, marsupials and ruminants. Here, I focus on the humble sheep – it serves as a model for human reproduction but has the added advantage of being important in industry. The sheep has helped us learn how the brain receives inputs about night length (photons), the odours of its flock mates (pheromones), the availability of food, and body status (eg, energy balance). The brain integrates all that information and enacts a strategy, fine-tuned over evolutionary timescales, to maximise reproductive success. My personal 4-decade scientific journey has been punctuated with unexpected discoveries that offered amazing new perspectives on reproductive biology. We used to think that brain cells cannot divide, but now we know that they do so in response to photons and pheromones. We used to accept a simple control system in which the brain produces a hormone that stimulates the gonads, but now we see brain-gonad communication as an intricate two-way exchange. We have discovered a plethora of control processes within the gonad – most astonishing, for me, being the ‘non-coding RNAs’ produced by DNA that interfere with the control of cells by genes. The implications? First, we are optimistic about the possibility of repairing brain tissue. Second, gone is the simple view that a gene produces RNA that produces a protein to control the cell, with non-coding RNAs offering a new suite of therapeutic possibilities. Third, photons, pheromones and food have presented ‘clean, green and ethical’ managementt of livestock – a complete about-turn in the thinking that dominated research on livestock reproduction when our Society first met in 1968.