Parasites are a major force in evolution, and understanding how host life history affects parasite pressure and investment in disease resistance is a general problem in evolutionary biology. The threat of disease may be especially strong in social animals, and ants have evolved the unique metapleural gland (MG), which in many taxa produce antimicrobial compounds that have been argued to have be...

Many attempts have been made to understand the origin of life and biological complexity both at the experimental and theoretical levels but neither is fully explained. In an influential work, Maynard Smith and Szathmáry (1995) argued that the majority of the increase in complexity is not gradual, but it is associated with a few so-called major transitions along the way of the evolution of life....

Progression through the eukaryotic cell cycle is characterized by specific transitions, where cells move irreversibly from stage i-1 of the cycle into stage i. These irreversible cell cycle transitions are regulated by underlying bistable switches, which share some common features. An inhibitory protein stalls progression, and an activatory protein promotes progression. The inhibitor and activa...

Objectives: The stages of change component of the transtheoretical model has been applied to safe sex behaviours in cross-sectional analyses, but have not yet been subject to prospective analysis. It was predicted that: (a) cross-sectional analyses would demonstrate good discrimination between the stages of change, (b) prospective analyses would allow for the identification of predictors of sta...

Life-history transitions require major reprogramming at the behavioral and physiological level. Mating and reproductive maturation are known to trigger changes in gene transcription in reproductive tissues in a wide range of organisms, but we understand little about the molecular consequences of a failure to mate or become reproductively mature, and it is not clear to what extent these processe...

OBJECTIVES The stages of change component of the transtheoretical model have been applied to safe sex behaviours in cross-sectional analyses, but have not yet been subject to prospective analysis. It was predicted that: (a) cross-sectional analyses would demonstrate good discrimination between the stages of change; (b) prospective analyses would allow for the identification of predictors of sta...

The guidelines, authored by a Task Force of experts in feline clinical medicine, are an update and extension the AAFP–AAHA Feline Life Stage Guidelines published 2010. guidelines simultaneously Journal Medicine Surgery (volume 23, issue 3, pages 211–233, DOI: 10.1177/1098612X21993657) American Animal Hospital Association 57, 2, 51–72, 10.5326/JAAHA-MS-7189). A noteworthy change from earlier is ...

BACKGROUND Later transitions to adult roles and responsibilities have been linked with better psychological well-being yet psychological distress has risen despite young people making the transition to adulthood at older ages over recent years. METHOD We examine the role of structural constraints and adolescent resources in the relationship between the timing of transitions and psychological ...