Experimental manipulation of body size alters life history in hydra

Body size has fundamental impacts on animal ecology and physiology but been strongly influenced by recent climate change human activities, such as size-selective harvesting. Understanding the ecological life history consequences of body proved difficult due to inseparability direct effects from processes connected it (such growth rate individual condition). Here, we used cnidarian Hydra oligactis directly manipulate understand its causal reproduction senescence. We found that experimentally reducing delayed sexual development lowered fecundity, while post-reproductive survival increased, implying smaller individuals can physiologically detect their reduced adjust decisions achieve higher survival. Our experiment suggests or human-induced changes in will have immediate population dynamics through a growth-independent link between size,