Life in the really slow lane : loggerhead sea turtles mature late relative to other reptiles

1. Age at maturity is hard to estimate for species that cannot be directly marked or observed throughout their lives and yet is a key demographic parameter that is needed to assess the conservation status of endangered species. 2. For loggerhead turtles (Caretta caretta) in the North Atlantic and North Pacific, juvenile growth rates (c. 10 cm year−1) were calculated by examining size increases during transoceanic journeys; durations of which were estimated from satellite-tracked Lagrangian surface drifter buoy trajectories. 3. Lagrangian-derived growth estimates were used in a weighted loglinear model of size-specific growth rates for loggerhead turtles and combined with newly available information on size at maturity to estimate an age at maturity of 45 years (older than past estimates). 4. By examining the age at maturity for 79 reptile species, we show that loggerhead turtles, along with other large-bodied Testudine (turtle and tortoise) species, take longer to reach maturity than other reptile species of comparable sizes. This finding heightens concern over the future sustainability of turtle populations. By maturing at an old age, sea turtles will be less resilient to anthropogenic mortality than previously suspected.

The sociological imaginary and disability enquiry in late modernity

Mills’s idea of the sociological imagination has captured many generations of scholars interested in the difficult social issues that people grapple with in their lives. Yet, sociology has traditionally had a poor record of linking disabled people’s ‘private’ accounts of their difficulties to ‘public’ issues. We contend that disability is still marginal to the sociological imaginary, despite attempts by disability studies and subdisciplines within sociology to make the concept relevant to the larger discipline. There is a range of conceptual tensions in sociology such as public/private and normal/abnormal that can be better illuminated by focusing on disability. We argue that critical disability studies, with its reimagining of disability within late modernity, may be better positioned to make more effectively the case for disability’s significance to the sociological imaginary. Facilitating dialogue with sociology on the concept of disability, however, may require disability scholars to develop more explicit strategies of engagement.

Late maturers at a performance disadvantage to their more mature peers in junior Australian football

Children and adolescents mature at different rates such that individuals competing in the same competition may differ in physical and biological maturity despite being of similar chronological age. Whether or not differences translate into on-field performance in competition is relatively unknown. This study investigated the influence of biological maturity on fitness and match running performance in junior Australian football. Eighty-seven under-15 years players were categorised into early (n = 20), average (n = 45) and late (n = 22) maturity groups based on self-reported and anthropometric assessment of biological maturity. Running movements during competition were collected using GPS (5 Hz) technology. Early maturers were heavier and taller than all other boys (P < 0.05), while biological maturity was significantly correlated to 20 m sprint (r = 0.53, P < 0.01). Total distance, high-intensity (>14.4 km · h−1) running distance and number of high-intensity efforts were significantly greater (20.8%, 53.6%, 31.7%, respectively; P < 0.01) in early compared to late maturers. Number of sprints and peak speed in competition were not different. Pubertal development and maturity status partially explained the differences between players in physical size, functional running fitness and match running performance. Late maturing players in this Australian football under-15 age group were at a physical and performance disadvantage to their earlier maturing peers.

Did the late-2000s financial crisis influence construction labour productivity?

The late-2000s global financial crisis has wrought dramatic impacts on the construction industry. However, the issue of whether the crisis influenced the behaviours of the construction industry has not been addressed yet. This research presents an econometric approach to investigating the effects of the recent global financial crisis on construction labour productivity. By employing the error correction model and panel regression methods, the direct and indirect effects of the financial crisis on the changes in Australian construction labour productivity are explored at national and state levels. Neither the direct nor the indirect effects appear statistically significant. The results indicate that the direct effect of the financial crisis drives up construction labour productivity at the national level, while the indirect effect diminishes productivity. The effects of the financial crisis on the state construction labour productivity vary from state to state. The financial crisis influenced construction labour productivity directly and significantly in the northern and eastern regions, while the direct effects appear not significant in the other states and territories. The indirect effects of the financial crisis on productivity are statistically significant in three regions: the Australian Capital Territory, the Northern Territory and Western Australia. By comparison, the model with the financial effects fails to provide more accurate simulating results. As such, this research concludes that the influence of the late-2000s financial crisis on Australian national and state construction labour productivity is limited.

Late Permian marine ecosystem collapse began in deeper waters: Evidence from brachiopod diversity and body size changes

Analysis of Permian-Triassic brachiopod diversity and body size changes from different water depths spanning the continental shelf to basinal facies in South China provides insights into the process of environmental deterioration. Comparison of the temporal changes of brachiopod diversity between deepwater and shallow-water facies demonstrates that deepwater brachiopods disappeared earlier than shallow-water brachiopods. This indicates that high environmental stress commenced first in deepwater settings and later extended to shallow waters. This environmental stress is attributed to major volcanic eruptions, which first led to formation of a stratified ocean and a chemocline in the outer shelf and deeper water environments, causing the disappearance of deep marine benthos including brachiopods. The chemocline then rapidly migrated upward and extended to shallow waters, causing widespread mass extinction of shallow marine benthos. We predict that the spatial and temporal patterns of earlier onset of disappearance/extinction and ecological crisis in deeper water ecosystems will be recorded during other episodes of rapid global warming.