Circadian biology: clocks for the real world.

The circadian system of Neurospora crassa includes a molecular feedback loop that is entrainable by light. A recent study has shown that a second, elusive oscillator interacts with the feedback loop to drive output rhythms.     

Scale and conservation planning in the real world

Conservation planning is carried out on a variety of geopolitical and biogeographical scales. Whereas considerable consensus is emerging about the most appropriate procedures for identifying conservation areas, the spatial implications of conducting conservation planning at divergent scales have received little attention. Here we explore the consequences of planning at different geopolitical scales, using a database of the mammalian fauna from the Northern Provinces of South Africa. The conservation network resulting from treating the region as one unit is compared with networks generated separately for the provinces nested in that region. These outcomes are evaluated in terms of (i) their land use efficiencies, (ii) their spatial overlap, and (iii) the impact of algorithm attributes. Although land use efficiencies are greater on broader scales, on average the spatial congruence between the broad-scale regional network and fine-scale provincial networks was less than 14%. Algorithms using different selection rules fail to improve this disturbing outcome. Consequently, scale has an overwhelming influence on areas identified as conservation networks in geopolitical units. This should be recognized in conservation planning.     

Model phylogenies to explain the real world

Phylogenetic trees based on gene sequence data contain information about the evolutionary processes responsible for their genesis. Methods have now been developed which help to reveal those processes. The methods are based on simple models of evolutionary change but, when applied across individuals in a population, rather than across species in a higher-level taxon, they can reveal the past history of population change. Examples from salamanders and viruses are used to illustrate how the past history of changes in speciation rate and the origin of epidemics can be inferred in the absence of fossil material or historical documentation.     

Running in the real world: adjusting leg stiffness for different surfaces.

A running animal coordinates the actions of many muscles, tendons, and ligaments in its leg so that the overall leg behaves like a single mechanical spring during ground contact. Experimental observations have revealed that an animal''s leg stiffness is independent of both speed and gravity level, suggesting that it is dictated by inherent musculoskeletal properties. However, if leg stiffness was invariant, the biomechanics of running (e.g. peak ground reaction force and ground contact time) would change when an animal encountered different surfaces in the natural world. We found that human runners adjust their leg stiffness to accommodate changes in surface stiffness, allowing them to maintain similar running mechanics on different surfaces. These results provide important insight into mechanics and control of animal locomotion and suggest that incorporating an adjustable leg stiffness in the design of hopping and running robots is important if they are to match the agility and speed of animals on varied terrain.     

Cpn20: Siamese twins of the chaperonin world

The chloroplast cpn20 protein is a functional homolog of the cpn10 co-chaperonin, but its gene consists of two cpn10-like units joined head-to-tail by a short chain of amino acids. This double protein is unique to plastids and was shown to exist in plants as well plastid-containing parasites. In vitro assays showed that this cpn20 co-chaperonin is a functional homolog of cpn10. In terms of structure, existing data indicate that the oligomer is tetrameric, yet it interacts with a heptameric cpn60 partner. Thus, the functional oligomeric structure remains a mystery. In this review, we summarize what is known about this distinctive chaperonin and use a bioinformatics approach to examine the expression of cpn20 in Arabidopsis thaliana relative to other chaperonin genes in this species. In addition, we examine the primary structure of the two homologous domains for similarities and differences, in comparison with cpn10 from other species. Lastly, we hypothesize as to the oligomeric structure and raison d’être of this unusual co-chaperonin homolog. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Bringing the real world into the biology curriculum

This study followed a small but diverse group of biology teachers through the first two years of the pilot for a new Advanced Level Biology course - Salters-Nuffield Advanced Biology. SNAB aims to modernise A-level Biology using real world contexts and examples as the starting point, promoting conceptual understanding rather than factual recall, encouraging active learning and developing a capacity for critical thinking and reflection. If the teachers were to implement this new curriculum as intended they would have to change some of their usual practices. The challenges which they encountered and the ways in which they responded were identified through a series of semi-structured interviews with each teacher, supported by lesson observations and interviews with students and technicians. A major constraint on changing practice was uncertainty about how to manage new approaches effectively.     

Adaptive monitoring in the real world: proof of concept

We recently proposed the adaptive monitoring approach for improving ecological monitoring, but to date no explicit examples exist. In this review, we demonstrate adaptive monitoring using two new case studies where pre-existing monitoring programs were redesigned to address new policy and scientific questions without breaching the integrity of past and ongoing time-series data. Lessons underpinning successful adaptive monitoring are: better recognition of the potential inter-relationships between adaptive monitoring and adaptive management to improve adoption of both; an understanding of what constitutes adaptive monitoring so that it is readily differentiated from ad hoc and reactive monitoring; and the forging of partnerships between researchers, policy-makers and resource managers to accommodate differences between policy-relevant and research-relevant questions and differences in conceptual models of ecosystem function, structure and management.     

Optimal adjustment of the human circadian clock in the real world

Which suggestions for behavioral modifications, based on mathematical models, are most likely to be followed in the real world? We address this question in the context of human circadian rhythms. Jet lag is a consequence of the misalignment of the body’s internal circadian (~24-hour) clock during an adjustment to a new schedule. Light is the clock’s primary synchronizer. Previous research has used mathematical models to compute light schedules that shift the circadian clock to a new time zone as quickly as possible. How users adjust their behavior when provided with these optimal schedules remains an open question. Here, we report data collected by wearables from more than 100 travelers as they cross time zones using a smartphone app, Entrain. We find that people rarely follow the optimal schedules generated through mathematical modeling entirely, but travelers who better followed the optimal schedules reported more positive moods after their trips. Using the data collected, we improve the optimal schedule predictions to accommodate real-world constraints. We also develop a scheduling algorithm that allows for the computation of approximately optimal schedules "on-the-fly" in response to disruptions. User burnout may not be critically important as long as the first parts of a schedule are followed. These results represent a crucial improvement in making the theoretical results of past work viable for practical use and show how theoretical predictions based on known human physiology can be efficiently used in real-world settings.