Zebra finch illustration by Ilse Schrauwers (https://isontwerp.nl)

We need more energy as we age

Briga, Michael ; Verhulst, Simon In humans and in wild mammals and birds, the functioning of our bodies declines with age. Understanding how our organisms age and how this ageing associates with lifespan is crucial for improving our quality of life and lifespan. Our rate of energy consumption or metabolism determines many aspects of our activity, physiology, behaviour and personality. We know that in mammals … Continue reading We need more energy as we age

Male Anna’s hummingbird (Calypte anna). Photo credit: Tony Varela Photography

When do hummingbirds use torpor? Body size and the environment make a difference

Spence, Austin; Tingley, Morgan Hummingbirds need a lot of energy. Their resting body temperature is around 40º C and their main method of flying, hovering, requires more energy than any other form of locomotion. Despite these energetic requirements, hummingbirds live across North and South America at a wide range of elevations. To live in these diverse environments while managing their energy needs, hummingbirds use a … Continue reading When do hummingbirds use torpor? Body size and the environment make a difference

Effects of plant hydraulic traits on the flammability of live fine canopy fuels

Scarff, Fiona; Lenz, Tanja; Richards, Anna; Zanne, Amy; Wright, Ian; Westoby, Mark Plants need to regulate water content of their tissues, and each species addresses this challenge in its own characteristic way. Different strategies mean that some plants will be wetter during the hot, dry weather associated with wildfires. Wildfires are confined to a smaller area when they burn through moist fuels so, if species … Continue reading Effects of plant hydraulic traits on the flammability of live fine canopy fuels

Relationship between heat hardening capacity of Sinonovacula constricta and seasonal temperature variation. (a) The frequency of operative temperatures that S. constricta experienced in the intertidal mudflat as measured by buried roboclams; arrows point to the maximum temperature recorded. (b) Effects of heat hardening in shifting the Arrhenius break temperature (ABT) of S. constricta after heat stress treatments of clams collected in June, September, December and April, respectively. (c) Comparable data for flatline temperature (FLT). Red circles indicate significant increases in ABT or FLT and the blue circle indicates a significant decrease. The red short line (–) indicates no significant change in ABT or FLT caused by heat hardeninghide

Synchronization of seasonal acclimatization and short-term heat hardening improves physiological resilience in a changing climate

Dong, Yun-wei; Zhang, Wenyi; Storey, Kenneth Anthropogenic global warming is one of the biggest environmental problems at present and how organisms cope with the rising temperatures raises more and more concerns. To understand the capability of organisms to survive future warming, it is important to study their physiological plasticity, the ability to adjust thermal tolerance to deal with high temperature. Physiological plasticity can take place … Continue reading Synchronization of seasonal acclimatization and short-term heat hardening improves physiological resilience in a changing climate

Free-ranging male and female American alligator (Alligator mississippiensis) in courtship (Credit: Kristen Zemaitis).

The immune costs of testosterone: can males break even?

Ezenwa, Vanessa; LaVere, Ashley; Hamlin, Heather; Lowers, Russell; Parrott, Benjamin When you think about animal courtship, you may picture an ostentatious male strutting around to impress a group of females, like a peacock displaying its tail feathers; or two males fighting for a female’s favor, like two rams butting heads to show their strength. Although elaborate displays and acts of aggression may help a male … Continue reading The immune costs of testosterone: can males break even?