In some species, egg-laying moms construct elaborate nests, burrows, or hiding spots for egg incubation. In other species, embryos are attached to the mother’s body in a specialized pouch or in a crevasse on her body. For some, the embryos are carefully guarded until they hatch. The type and extent of egg care is largely dictated by the ecology of the species in question and by the order in which egg extrusion and fertilization occur.
The environment can do a lot of things to increase your chances of sexual success, when used wisely. These species use the sun to help improve the impact of their mating signals. Using the sun’s light to impress a mate Great bustard males augment illumination of their white plumage by pointing it at the sun. This maximizes the contrast of their achromatic (white) feathers against the dark background of their habitat. Photo via AdobeStock Iridescent
Christmas tree worms are so named because these marine worms have colourful spiral plumes that resemble a Christmas tree! They come in a variety of colours, like red, orange, pink, blue, white, yellow, and brown. Photo by Klaus Torsten Klaeden The “Christmas trees” are in pairs, attached to the same worm. The plumes are radioles — hair-like appendages — measuring about 1.5 inches in length. Each worm has two of these “Christmas trees” to catch
Through an asexual reproduction process called parthenogenesis or thelytoky, several species of females can produce genetic clones of themselves. Image by Arek Socha from Pixabay This process does not require a genetic contribution from a male (sperm). However, most parthenogenetic females can also reproduce sexually when the opportunity presents itself. In fact, a female may choose a complex course of reproductive options depending on the environmental cues that she experiences at a given time. When
Naked mole rats live mostly underground in elaborate tunnels. They rarely come above ground for any reason other than to obtain food, defend the colony, or, in rare cases, found a new colony. Unlike the subordinate female meerkats, who are fertile but do not reproduce, all subordinate female naked mole rats are infertile. A specific chemical cue contained in the urine of the single dominant female keeps all other females from reaching reproductive maturity. In
The largest species of freshwater fish in North America also has the longest lifespan. The White Sturgeon can reach lengths of over 6 meters and live for over 150 years. Sturgeon fossils have been discovered from the mid-Jurassic period, and these ancient fish have remained relatively unchanged for millions of years. Photo by the Oregon Department of Fish and Wildlife Instead of scales, White Sturgeon have bony plates called scutes arranged in rows down its
postpartum depression
Postpartum depression is a depression which extends past the point of days or even weeks after giving birth. The physiological changes associated with postpartum depression are very real. They reinforce each other in a cyclical way. Stress causes high corticosterone, which results in lower levels of oxytocin. As a result, these low levels make mom feel worse and more stressed, and so the cycle continues. Postpartum depression is not something to be dismissed or belittled.