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Climate change and size-selective overexploitation can alter fish size and growth, yet our understanding of how and to what extent is limited due to a lack of long-term biological data from wild populations. This precludes our ability to effectively forecast population dynamics and support sustainable fisheries management. Using modern, archived, and archaeological vertebrae dimensions and growth rings of one of the most intensely exploited populations, the eastern Atlantic and Mediterranean bluefin tuna (Thunnus thynnus, BFT), we estimated catch-at-size and early-life growth patterns from the 3rd century bce to the 21st century ce to understand responses to changes in its environment. We provide novel evidence that BFT juvenile growth increased between the 16th–18th, 20th, and 21st centuries, and is correlated with a warming climate and likely a decrease in stock biomass. We found it equally plausible that fisheries-induced evolution has acted to increase juvenile BFT growth, driving earlier maturation as a result of size-selective exploitation. Coincidently, we found limited evidence to suggest a long history of large ( >200 cm FL) BFT capture. Instead, we found that the catch-at-size of archaeological BFT was relatively small in comparison with more intensive, 20th and 21st century tuna trap fisheries which operated further from shore. This complex issue would benefit from studies using fine-scale biochronological analyses of otoliths and adaptation genomics, throughout the last century especially, to determine evolutionary responses to exploitation, and further disentangle the influence of temperature and biomass on fish growth.

This paper presents a zooarchaeological analysis from the site of Spolverino (southern Tuscany, Italy). Archaeological excavations have uncovered a complex stratigraphy dated from the Roman Imperial period to Late Antiquity (late 1st- early 6th centuries AD). The industrial function of the site in Imperial times is partially reflected in the nature of the faunal assemblage. In Late Antiquity, Spolverino lost its original manufacturing functions, as many of the workshops were abandoned; our evidence, however, suggests that some livestock was kept, probably managed by a restricted group of people still living in that area. Some hunting was practiced throughout the occupation but it increased in the later periods. Remarkable, in Late Antiquity, is the occurrence of the fallow deer, an introduced species, rare in Roman contexts.