mammals

 

Common disinfectants impair mouse fertility

Posted 11 November 2014 by Anne-Marie Hodge

Hey everyone, I recently wrote an article on a new toxicology study for The Conversation, and they have kindly allowed me to repost the piece on SciLogs in its entirety. Read on to find out about how two research labs that shared an annoying mouse attrition problem joined forces to make an important discovery about chemicals found in nearly every home in the U.S. Mice possess a notable talent: they are excellent at making more mice. Their ability to reproduce... Read more

The Poop Scoop: Using Feces to Track Ebola Infection and Survival Wild Apes

Posted 29 September 2014 by Anne-Marie Hodge

Prologue: In case you have been completely isolated from the news in recent months, here’s a recap: West Africa (principally Sierra Leone, Liberia, Senegal, Guinea and Nigeria) is experiencing an unprecedentedly wide outbreak of Ebola, and the epidemic continues to snowball with each passing day. Medical treatments in most developed countries could likely contain or limit such an outbreak (we hope), but under-resourced West and Central African countries have not been able to curb the spread of the virus. Historically, the mortality rate... Read more

Promiscuity Breeds Efficiency: Mouse Mating Systems Affect Sperm Sprints

Posted 17 August 2014 by Anne-Marie Hodge

Sperm is constant joke-fodder. From the opening credits of the movie "Look Who's Talking" to various Shakespeare passages, we humans never seem to tire of laughing at hordes of competitive little sperm powering past each other in the race towards their final destination. They're unbelievably tiny, simple entities, and yet the outcome of their performance is huge. Or perhaps we just stay fascinated by the dramatic fact that all of our lives began when one of those little guys won a race that has been going on since... Read more

Stress Promotes Skin-Healing in Mice

Posted 10 August 2014 by Anne-Marie Hodge

Everyone has experienced the effects of stress: fidgeting, sweating, inability to focus, gain or loss of appetite, racing heartbeat, and so on. All of these things can happen to us when the adrenal system releases "stress hormones," a process that often disrupts many aspects of daily life. We don't like it. Our aversion to stress has sparked a cottage industry of self-help books, seminars, podcasts, videos, and various therapies that claim to teach us how to chill out and stay calm.   Although the "symptoms" of stress make... Read more

The Enemy of My Enemy Means More Food–Monkeys Use Human Shields

Posted 29 July 2014 by Anne-Marie Hodge

The human species is a major driver of biodiversity loss across the globe. Occasionally, however, that propensity for extermination can become an advantage for animals that associate with us. What could be better protection from competing species than the presence of a menace that threatens wildlife? Sometimes, being the enemy of an enemy can turn us into a "friend"--or at least the lesser of two evils. This issue was highlighted in recent study involving the samango monkey (Cercopithecus mitis erythrarcus),... Read more

Does Sloth Fur Fungus Hold the Next “Wonder Drug?”

Posted 28 January 2014 by Anne-Marie Hodge

Throughout human history, humans have included wild animals in their folklore, mythology, and daily vocabulary. Animals with especially distinctive traits have likewise become ensconced in modern popular culture and language. Leonine features are considered striking and sexy, outfoxing someone is a demonstration of cleverness, and it is obnoxious to parrot someone in a conversation. Being slothful is unlikely to gain you any respect. Sloths spend the vast majority of their lives nearly sedentary, moving through the canopy at incremental paces.... Read more

Life in the slow lane: Primate metabolisms run at half the pace of other mammals

Posted 22 January 2014 by Anne-Marie Hodge

  Western society is obsessed with metabolism. Magazines bombard us with splashy headlines offering hyperbolic advice on how to boost, rev, fire up, jump-start, enhance, or otherwise maximize our metabolic rates. You should eat six meals a day, or fast two days a week, or drink green tea before every meal, or sleep 9 hours a night, or hang upside down, or use company X’s proprietary powder/capsule/plant-extract to ensure that your metabolism is purring along like a jet. We are... Read more

The Case of the Heterodox Fox: Bergmann’s Rule North and South of the Equator

Posted 11 August 2013 by Anne-Marie Hodge

Ecology is a mind-bogglingly complex field. As such, ecologists make few "rules"--they're more like "tentative tenets." Nature presents an exception for nearly everything, so even "rules" are often framed less as absolute laws and more as hypotheses to continue testing. One of the best-known "rules" of evolutionary ecology, is Bergmann’s rule, which predicts that endothermic animals found in cooler climates will have larger body sizes than conspecific populations or closely-related species in warmer habitats (Bergmann 1847). Bergmann’s reasoning was that... Read more

Hibernating Bears Run Hotter and Cleaner While Pregnant

Posted 3 August 2013 by Anne-Marie Hodge

When it comes to feats of physiology, bears are among the superstars of the mammalian world. Their endurance is legendary. During hibernation, bears regularly survive up to six full months without consuming any food at all. Hibernating bears reduce their heart rates by over 80% and decrease their metabolic rates by 50-75%, yet they actually remain conscious during this time (Laske et al. 2010; Tøien et al. 2011). Bears also manage to avoid muscle atrophy and loss of bone density,... Read more

Brains Versus Brawn Amongst Wild Canids

Posted 8 April 2013 by Anne-Marie Hodge

Continuing the theme from my last post, I'm going to cover a new study involving some of the carnivores that I'm observing and studying out here in Kenya. Last time we talked about mongoose, and this time we'll move on to one of my favorite mammalian families: the Canidae. Few things are more important for a carnivore's survival than having a lethal bite. The critical mechanics underlying bite force have significantly influenced carnivore evolution--they determine morphology, hunting behavior, and prey... Read more