As well as being required to make reliable assessments about sexual partners based on their physical and behavioural characteristics, animals (humans included) need to have the ability to revise these assessments based on any number of confounding environmental variables. Plasticity refers to both variability in ecological or biological factors, and variability in behavioural or physiological reactions that animals exhibit. Context Dependence If anyone asks me about the most comfortable bed I’ve ever slept in, the
Animal personalities are not simply a matter of aggressive versus non-aggressive types. There is a substantial diversity in the kinds of behaviours that define a temperament, and attractiveness need not be associated with being tough or being weak. Female zebra finches (Taeniopygia guttata) appear to choose partners based on their level of exploratory behaviour, as do male great tits (Parus major). Photo via Adobe Stock Both these bird species are bi-parental and socially monogamous, meaning
Bottlenose dolphin moms give birth in an open environment. Newborn dolphins remain very close to their mothers for the first few weeks after birth. Photo via Adobe Stock Echelon Swimming Something called echelon swimming takes place for at least the first week. During this time, the newborn receives physical support from its mother. The neonate is led along by its mother, almost draped over her head area. The two come to the surface to breathe
A couple of weeks ago, I streamed a live chat on Facebook between myself and Dr. Emily Willingham, journalist and science writer, who recently published the book Phallacy: Life Lessons From The Animal Penis. I absolutely loved the book. One thing that immediately grabbed me was how Emily really grabbed the interpretation and general thoughts about sexuality, penises, and the fallacy of the phallus, and turned it on its head! It was such a wonderful
The New World monkeys of Central and South America, tamarins and marmosets, are the main groups of cooperatively breeding primates. These are collectively known as callitrichids, and they inhabit many areas of Central and South America and share many characteristics that render them good candidates for cooperative breeding. Females always give birth to twins, which are dizygotic but that share a placenta. Photo via Adobe Stock Adult callitrichids are small, so a twin birth represents

October 28, 2020

The Importance of Colostrum

Milk pretty much picks up where the placenta left off in terms of how a mammalian infant is provisioned by its mom. The most energetically demanding time for infants, the period just after birth, coincides with the transition of physiological transfer of nutrients being very efficient via the placenta to being much less efficient via lactation. Where biochemical messages were once transferred between mom and baby through intimate placental connections, such messages were once transferred
As members of a species with separate sexes, humans tend to forget about the suite of organisms out there that are hermaphrodites, simultaneously carrying male and female genitalia. Hermaphroditism is present in 24 of the 34 animal phyla (taxonomic groups), and is quite common in the invertebrate world. In fact, for many organisms hermaphroditism is the rule rather than the exception. Photo via Adobe Stock When animals are both male and female at the same