Biological Reviews of the Cambridge Philosophical Society

The loss of functional β cells leads to development of diabetes. Several studies have shown that β cells are specified through several stages of progenitors during pancreas development, each stage defined by the expression of specific transcription factors (TFs). Understanding signalling pathways that control the differentiation and specification processes during embryogenesis will facilitate efforts to obtain functional β cells in vitro. Our current knowledge of the mechanisms involved in pancreatic β cell development and survival under normal or diabetic conditions has come largely from animal studies...

The respiratory chain of mitochondria and bacteria is made up of a set of membrane-associated enzyme complexes which catalyse sequential, stepwise transfer of reducing equivalents from substrates to oxygen and convert redox energy into a transmembrane protonmotive force (PMF) by proton translocation from a negative (N) to a positive (P) aqueous phase separated by the coupling membrane. There are three basic mechanisms by which a membrane-associated redox enzyme can generate a PMF. These are membrane anisotropic arrangement of the primary redox catalysis with: (i) vectorial electron transfer by redox metal centres from the P to the N side of the membrane; (ii) hydrogen transfer by movement of quinones across the membrane, from a reduction site at the N side to an oxidation site at the P side; (iii) a different type of mechanism based on co-operative allosteric linkage between electron transfer at the metal redox centres and transmembrane electrogenic proton translocation by apoproteins...

Bone formation, for example during bone remodelling or fracture repair, requires mature osteoblasts to deposit bone with remarkable spatial precision. As osteoblast precursors derive either from circulation or resident stem cell pools, they and their progeny are required to migrate within the three-dimensional bone space and to navigate to their destination, i.e. to the site of bone formation. An understanding of this process is emerging based on in vitro and in vivo studies of several vertebrate species. Receptors on the osteoblast surface mediate cell adhesion and polarization, which induces osteoblast migration...

Ecological studies are increasingly moving towards trait-based approaches, as the evidence mounts that functions, as opposed to taxonomy, drive ecosystem service delivery. Among ecosystem services, biological control has been somewhat overlooked in functional ecological studies. This is surprising given that, over recent decades, much of biological control research has been focused on identifying the multiple characteristics (traits) of species that influence trophic interactions. These traits are especially well developed for interactions between arthropods and flowers - important for biological control, as floral resources can provide natural enemies with nutritional supplements, which can dramatically increase biological control efficiency...

Climate change is driving a pervasive global redistribution of the planet's species. Species redistribution poses new questions for the study of ecosystems, conservation science and human societies that require a coordinated and integrated approach. Here we review recent progress, key gaps and strategic directions in this nascent research area, emphasising emerging themes in species redistribution biology, the importance of understanding underlying drivers and the need to anticipate novel outcomes of changes in species ranges...

We synthesize findings from one of the world's largest and longest-running experimental investigations, the Biological Dynamics of Forest Fragments Project (BDFFP). Spanning an area of ∼1000 km(2) in central Amazonia, the BDFFP was initially designed to evaluate the effects of fragment area on rainforest biodiversity and ecological processes. However, over its 38-year history to date the project has far transcended its original mission, and now focuses more broadly on landscape dynamics, forest regeneration, regional- and global-change phenomena, and their potential interactions and implications for Amazonian forest conservation...

An exhaustive study of existing data on the relationship between egg size and maximum size of embryonic shells in 42 species of extant cephalopods demonstrated that these values are approximately equal regardless of taxonomy and shell morphology. Egg size is also approximately equal to mantle length of hatchlings in 45 cephalopod species with rudimentary shells. Paired data on the size of the initial chamber versus embryonic shell in 235 species of Ammonoidea, 46 Bactritida, 13 Nautilida, 22 Orthocerida, 8 Tarphycerida, 4 Oncocerida, 1 Belemnoidea, 4 Sepiida and 1 Spirulida demonstrated that, although there is a positive relationship between these parameters in some taxa, initial chamber size cannot be used to predict egg size in extinct cephalopods; the size of the embryonic shell may be more appropriate for this task...

While empathy is a century-old psychological concept, its study in non-human animals has become the focus of much recent scientific interest, as it promises to provide the clues to understand the evolutionary origins of our social and moral nature. A review of the comparative study of empathy is thus timely to complement and constrain anthropocentric views, and to integrate current findings. However, this is not an easy task. The study of animal empathy has developed using different paradigms, different concepts of the phenomena involved, and the absence of a systematic program...

The evolution of plastids has a complex and still unresolved history. These organelles originated from a cyanobacterium via primary endosymbiosis, resulting in three eukaryotic lineages: glaucophytes, red algae, and green plants. The red and green algal plastids then spread via eukaryote-eukaryote endosymbioses, known as secondary and tertiary symbioses, to numerous heterotrophic protist lineages. The number of these horizontal plastid transfers, especially in the case of red alga-derived plastids, remains controversial...

More than a century ago, William Morton Wheeler proposed that social insect colonies can be regarded as superorganisms when they have morphologically differentiated reproductive and nursing castes that are analogous to the metazoan germ-line and soma. Following the rise of sociobiology in the 1970s, Wheeler's insights were largely neglected, and we were left with multiple new superorganism concepts that are mutually inconsistent and uninformative on how superorganismality originated. These difficulties can be traced to the broadened sociobiological concept of eusociality, which denies that physical queen-worker caste differentiation is a universal hallmark of superorganismal colonies...

Odorant-binding proteins (OBPs) and chemosensory proteins (CSPs) are regarded as carriers of pheromones and odorants in insect chemoreception. These proteins are typically located in antennae, mouth organs and other chemosensory structures; however, members of both classes of proteins have been detected recently in other parts of the body and various functions have been proposed. The best studied of these non-sensory tasks is performed in pheromone glands, where OBPs and CSPs solubilise hydrophobic semiochemicals and assist their controlled release into the environment...

In the past decade, research on long-term persistence of phytoplankton resting stages has intensified. Simultaneously, insight into life-cycle variability in the diverse groups of phytoplankton has also increased. Aquatic 'seed banks' have tremendous significance and show many interesting parallels to terrestrial seed beds of vascular plants, but are much less studied. It is therefore timely to review the phenomenon of long-term persistence of aquatic resting stages in sediment seed banks. Herein we compare function, morphology and physiology of phytoplankton resting stages to factors central for persistence of terrestrial seeds...

Functional traits have been fundamental to the evolution and diversification of entire fish lineages on coral reefs. Yet their relationship with the processes promoting speciation, extinction and the filtering of local species pools remains unclear. We review the current literature exploring the evolution of diet, body size, water column use and geographic range size in reef-associated fishes. Using published and new data, we mapped functional traits on to published phylogenetic trees to uncover evolutionary patterns that have led to the current functional diversity of fishes on coral reefs...

In wild-type cells, autophagy represents a tumour-suppressor mechanism, and dysfunction of the autophagy machinery increases genomic instability, DNA damage, oxidative stress and stem/progenitor expansion, which are events associated with cancer onset. Autophagy occurs at a basal level in all cells depending on cell type and cellular microenvironment. However, the role of autophagy in cancer is diverse and can promote different outcomes even in a single tumour. For example, in hypoxic tumour regions, autophagy emerges as a protective mechanism and allows cancer cell survival...

Early environments can profoundly influence an organism in ways that persist over its life. In reptiles, early thermal environments (nest temperatures) can impact offspring phenotype and survival in important ways, yet we still lack an understanding of whether general trends exist and the magnitude of impact. Understanding these patterns is important in predicting how climate change will affect reptile populations and the role of phenotypic plasticity in buffering populations. We compiled data from 175 reptile studies to examine, and quantify, the effect of incubation temperature on phenotype and survival...

Key global indicators of biodiversity decline, such as the IUCN Red List Index and the Living Planet Index, have relatively long assessment intervals. This means they, due to their inherent structure, function as late-warning indicators that are retrospective, rather than prospective. These indicators are unquestionably important in providing information for biodiversity conservation, but the detection of early-warning signs of critical biodiversity change is also needed so that proactive management responses can be enacted promptly where required...

Fear of predation is a universal motivator. Because predators hunt using stealth and surprise, there is a widespread ability among prey to assess risk from chemical information - scents - in their environment. Consequently, scents often act as particularly strong modulators of memory and emotions. Recent advances in ecological research and analytical technology are leading to novel ways to use this chemical information to create effective attractants, repellents and anti-anxiolytic compounds for wildlife managers, conservation biologists and health practitioners...

We review the state of African ungulate taxonomy over the last 120 years, with an emphasis on the introduction of the polytypic species concept and the discipline's general neglect since the middle of the 20th century. We single out negative consequences of 'orthodox' taxonomy, highlighting numerous cases of neglect of threatened lineages, unsound translocations that led to lineage introgression, and cases of maladaptation to local conditions including parasitic infections. Additionally, several captive breeding programmes have been hampered by chromosome rearrangements caused by involuntary lineage mixing...

Early survival is highly variable and strongly influences observed population growth rates in most vertebrate populations. One of the major potential drivers of survival variation among juveniles is body mass. Heavy juveniles are better fed and have greater body reserves, and are thus assumed to survive better than light individuals. In spite of this, some studies have failed to detect an influence of body mass on offspring survival, questioning whether offspring body mass does indeed consistently influence juvenile survival, or whether this occurs in particular species/environments...

According to recent empirical studies, reproductive senescence, the decline in reproductive success with increasing age, seems to be nearly ubiquitous in the wild. However, a clear understanding of the evolutionary causes and consequences of reproductive senescence is still lacking and requires new and integrative approaches. After identifying the sequential and complex nature of female reproductive senescence, we show that the relative contributions of physiological decline and alterations in the efficiency of parental care to reproductive senescence remain unknown and need to be assessed in the light of current evolutionary theories of ageing...