When I was in graduate school I found myself drawn to the “old-fashioned” skills of classical zoology: observation of and experiments with living animals. I had, and still have, very little interest in the new-fangled high-tech methods of studying animals, and part of me strongly resents having to homogenize an animal to know what its…
Month: March 2015
Long live the queen!
This afternoon we inspected our Purple hive to check on how the queen is doing and see if they need more space for either brood or honey. For the past few weeks I’ve been able to smell that they’re making some very tasty honey (it smells like buttered popcorn) and we want to make sure that…
Oral examination
Anyone who went to graduate school in the sciences remembers what oral exams are like. I remember not having any fun at all in mine, and by the time I was dismissed I wasn’t sure what my own name was. Fortunately, that is all ancient history and now I get to spend my time performing…
Next step: Building a mouth
My oldest baby urchins have been actual sea urchins for eight days now. Their total age, counting from the time they were zygotes, is 58 days. When an animal undergoes a life history event as drastic as this metamorphosis, it can be tricky deciding how to determine its age. Do you count from when egg…
Learning to walk
Imagine spending your entire life up in the water column as a creature of the plankton. You use cilia to swim but are more or less blown about by the currents, never (hopefully!) encountering a hard surface, and feeding on phytoplankton and other particulate matter suspended in the water. Then, several weeks into your life’s…
Taking their sweet time
After much teasing and titillation, my urchin larvae have finally gotten down to the serious business of metamorphosis. It seems that I had jumped the gun on proclaiming them competent about a week ago, or maybe they were indeed competent and just needed to wait for some exogenous cue to commit to leaving the plankton for…
Crab feed(ing)!
Anybody who has visited one of the sandy beaches in California has probably seen kids running around digging up mole crabs (Emerita analoga). These crabs live in the swash zone at around the depth where the waves would be breaking over your ankles, moving up and down with the tide. They are bizarre little creatures,…
Competence
In the parlance of invertebrate zoologists, competence is the state of development when a larva has all of the structures and energy reserves it needs to undergo metamorphosis into the juvenile form. In the case of my sea urchins, this means that they have four complete pairs of arms, each with its own skeletal rod, and…