Who knew that the song Enter Sandman was actually about an interesting biological phenomenon? Turns out many aquatic and terrestrial mammals and birds actually sleep with one eye open! The corresponding hemisphere of the brain maintains wakefulness, while the other sleeps.
For instance, Mallards (pictured above) exhibit unihemispheric sleep as a way to keep an eye out for predators. Some aquatic mammals, such as cetaceans and manatees, keep one half of their brain awake to control surfacing for air while the other half sleeps.
The phenomenon of unihemispheric sleep has called into question the definition of sleep, its function, and whether it is even essential. Cool!
I stumbled upon the rabbit hole of unihemispheric sleep after watching this eerie video of sperm whales sleeping:
It appears that sperm whales undergo complete (bihemispheric?) sleep for 12 minute snaps, sleeping for just about 7% of their day, giving that whale the title of sleeping for the smallest percentage of their day out of any mammal (giraffes come in 2nd place with 8%).
This is why I love biology. Lets assume sleep is a biological necessity. Millions of years of evolution and adaptation has pulled this necessity in as many directions. From sleeping with half your brain at a time, or with the whole brain 7% to 80% of the day to everything in between. Biology is a healthy mix of ubiquitous phenomena and specialized solutions. Sometimes the hardest part is not clicking that one more wikipedia article all day.
I tried something new with my Intro Bio lab students this semester. Every week I would have a new “Fun science fact of the week”- something relatively contemporary that I found exciting and had a (sometimes admittedly weak) connection to the current lab. I remember when I took intro bio lab things could feel a little stale and cookie-cutter, so I incorporated this as a way to spice things up.
For example- The week Voyager 1 left our solar system we were dissecting fetal pigs. I used this as an opportunity to show the slides of human anatomy stored on the Voyager 1 and describe just how similar pigs and humans are on the inside. This turned into a really fun discussion about space travel and genetic engineering. When we were discussing photosynthesis I went into some fun properties of light and the speed of light… which turned into a discussion about relative velocity and time dilation
When we discussed niche space I brought up the Radiotrophic Fungi discovered in Chernobyl. We then started discussing evolution and the “speed” of evolution. See, the fun facts naturally transitioned into a back-and-forth discussion among the students and myself. This set the pace and mood for the lab, and what might have been a stale lecture started off on the right foot as a passionate discussion about something fun.
The original plan on my end was that I would also blog about these facts every week and share them here… but it turns out grad school is pretty darn time consuming and my time allocation skills need refinement. There is always next semester!
Well, the results are in. According to my teaching evaluations the fun facts of the week were a big hit! Students looked forward to what the fact would be every week and share them with their friends after lab. In fact, after a few weeks I even had students emailing me with facts (“Hey, did you see this cool science video? Did you hear about this new research?” etc.) So, I would say the fun fact experiment was a success- and not just from the student’s perspective. I would get excited to see students excited about the fun facts, and looking forward to teaching every week certainly made preparations and grading less of a hassle!
More fun facts on here soon, I promise.