Exploring the world through the mind of an octopus: review of Sy Montgomery's book

Coming off some recent books about neuroscience and animal cognition, I found The Soul of an Octopus by nature writer Sy Montgomery in the local library. I thought it fit my reading theme nicely, so I decided to give it a try.

Overall, the book is interesting and easy to read. Unlike the books I normally read, the organization is not centered around the scientific themes, but rather towards the author's experience of the wonders of the octopus. The book focuses on the author's visits to the New England Aquarium here in Boston as well as to a few other aquariums around the country (notably the Seattle aquarium, which hosts an octopus blind date on Valentine's Day). She also visits the cephalopod laboratory at Middlebury College, where researchers study octopus cognition using an array of mazes and puzzles.

Octopuses (one thing I learned is that this is the correct form of octopus as it is a Greek derivative, like hippopotamus) are incredibly developed in their cognition. Their nervous system is on par with mammals like dogs in terms of the numbers of neurons. This complexity makes them expert problem solvers – they can use tools to help them catch prey and they can figure out how to remove food from puzzle boxes. They are natural escape artists, which makes it difficult for aquarium staff to keep them caged. YouTube has lots of examples of daring octopus escapes.

I did want to point out a few of the interesting facts I learned from the book. Octopus taste receptors, which are on their suction cups, can pick up taste signals from at least 30 yards. This gives them an excellent sense of changes in their environment. They also have a powerful camouflaging ability, which allows them to change colors very quickly. In the wild, they use this in a variety of predator-prey interactions. In the aquarium setting, the color changes are an indicator of the octopus' mood.

Perhaps the most amazing thing I learned was about octopus ink, which is a complex mixture of molecules. Of course, the list includes melanin, which gives ink its characteristic color; it also contains molecules like tyrosinase, which can irritate the eyes and gills of the surrounding sea life. More surprisingly, tyrosinase has been reported to have effects on oxytocin and vasopressin levels, suggesting that octopus ink could calm the squirted prey. Ink also includes dopamine, a neurotransmitter often called the reward hormone. These features of ink suggest that ink isn't just for defensive purposes, but it may also be used to help them capture prey. This has been observed in some species of squid, but not in octopus.

The book spurred me to look into recent publications on cephalopod neural complexity. One notable paper in Cell shows that cephalopods like the octopus have an unusually high rate of RNA editing. The process is unique to the branch of cephalopods called the coleoids, which are behaviorally complex (some might label them as "smart"). In addition, the sites of genome editing occur most frequently in genes associated with the nervous system. These correlations suggest that the ability to edit their genome is what gives them their complexity. Surprisingly, these changes at the RNA level can be inherited. Of course, this ability has its price. While these cephalopods have greater plasticity of the proteins made by RNA, they have a decreased mutation rate in the protein coding regions of DNA, which is the more traditional fodder for evolutionary variation. For more information on this surprising ability, check out the coverage in The Atlantic and New Scientist.

These stories left me wondering what other sorts of mysteries can be found in the octopus, an organism that is often compared to an alien due to its ability to camouflage rapidly, its knack for squeezing into tight spaces, its unusual defense mechanisms, and its uncanny problem solving. I will be heading soon to the New England aquarium to catch a glimpse of one of the octopuses that the author describes and will keep an eye out for more primary research that explains the mysteries of this amazing creature.

She's a brainiac: taming my amygdala's response to neuroscience

Cerebellar neurons by Ramón y Cajal

The study of the brain has always seemed so inaccessible to me. There is something so meta about it that, frankly, it seems to me that only super advanced beings could think about how our thoughts are formed. I felt comfortable in my single cell universe of cell biology, and I felt like neuroscience was far too intricate and complicated for my brain to handle.

Last year, I started working at Cell Reports, which is a broad science, open access journal. We get submissions from every field of biology. I am a cell biologist by training, so my comfort zone is there, but by new journal has really pushed me to read even more broadly than my previous experience at BBA.

For me, neuroscience papers are harder to access, especially because I have a hard time distinguishing my lateral habenula from my amygdala. To solve this shortcoming, I decided it was time to do some immersion therapy. I've read a few popular science books about the brain before–most memorably Sam Kean's Dueling Neurosurgeons. More recently, I read The Genius of Birds, which taught me a lot about how scientists are approaching experiments with the brain and behavior. These experimental designs are ingenious (more evidence that neuroscientists are just smarter beings), but they can seem a bit funny at times (e.g., mouse behind the wheel). Recently, using high resolution brain imaging like fMRI has allowed researchers to map changes in the brain as people think about people or listen to different types of music or are under the effects of LSD.


To continue my immersion therapy, I have been trying to find good popular science books about the brain. Browsing my local book store, I came across The Brain: The Story of You, by David Eagleman, a neuroscientist and adjunct professor at Stanford University. The book, which is also a PBS series, includes some new research as well as some classic experiments in neuroscience. These classical approaches, which were very well cataloged in The Dueling Neurosurgeons, is to rely on patients that are missing part of their brain and see what sort of behaviors they exhibit. This is certainly a noninvasive approach, which could be considered as a physiologically relevant organ-specific knock out. The problem is that the brain is incredible plastic (that word means something very different in neuroscience) and so it can adapt to the limitations of a missing piece. The other problem is that there are a limited number of people with missing parts to their brains!


Luckily, advances in neuro-imaging and the advent of techniques like optogenetics, have allowed neuroscientists to stray from these classic experimental models. Of course, that doesn't keep Eagleman from telling the crazy stories reminiscent of Oliver Sacks and his contributions to Radiolab. For example, he tells the case of the man who lost his sight at 3 years old and had a stem cell therapy to restore his vision in middle age. The therapy restored the ability of his eyes to receive visual stimuli, but his brain needed to be re-trained to interpret the messages from the eyes. Another fascinating bit was about proprioception, which could be considered the sixth sense that controls your body position. You might not know you have it- until you lose it, but this is what allows us to have fluid movements like walking or biking. There are rare cases of people who have lost this sense and the affected individual has to think carefully when moving and must train themselves to be able to move with some degree of fluidity.

While The Brain probably isn't the best book on the subject, it is very accessible and fun to read and certainly has helped in my immersion therapy. While I can now remember what the amygdala does, I'm still shaky about the lateral habenula or the nucleus accumbens, suggesting that my immersion therapy should continue.

The Genius of Birds teaches us that "bird brained" is a misnomer

Shortly after discovering the Great Backyard Bird Count last year, I started to realize what a perfect hobby birding could be for me. There is something in the process that appeals to me–both as a biologist and as a lover of lists. Unfortunately, I have not had as much time to develop my skills as a birder as I would like. Instead, I take a multi-tasking approach to the hobby as I look for birds on my runs or bike rides or from the comfort of my front porch. My newfound interest also inspired me to expand my reading list from the typical molecular and cell biology.

Enter The Genius of Birds by Jennifer Ackerman. The book explores the wonders of bird behaviors and cognition (a more scientific and less nebulous term for intelligence) and explores the latest research to understand how birds accomplish their unique feats of memory and critical thinking. Just as Lab Girl gave me a new appreciation for trees, The Genius of Birds gave me a new perspective on the birds around us.

Ackerman convinced me that "bird brained" is truly a misnomer. While birds do have small brains, they are densely packed with neurons and neural connections. Some birds are smarter than others. Corvids, the family that include crows, ravens, and parrots, are on the Einstein end of the spectrum, while quails, ostriches, and turkeys are on the Cletus the Slack-jawed yokel end. (Ackerman is always quite generous when writing of the simpler birds and would never be so pejorative with her subjects. She suggests that we just haven't observed the brilliance of these birds yet.) Crows have been considered smart since the time of Aesop, whose fable The Crow and the Pitcher highlights the type of problem solving that scientists enjoy exploring with these animals. The internet is filled with the fun stories about corvids and their feats of genius, like collecting gifts for people who feed them and even using tools. This genus has developed a reputation for clever and innovative behavior. Neuroscientists even use corvids as a model organism to better understand human cognition.

Aves is a large and diverse class of animals and each member has a unique set of skills, which Ackerman deftly and comprehensively illustrates. While corvids excel at problem solving, parrots and mockingbirds have exceptional skills in language. Bower birds have a strong artistic eye: the male constructs elaborate nests to entice females, who are able to discern even subtle differences in these ornate bowers. Other birds are expert navigators and map makers.

Even the common sparrow is a star in terms of its ability to adapt to humans and use our presence to further its species. The house sparrow is present on every continent except Antarctica, and is thought to have expanded its ecological range in parallel with humans. Surprisingly, the sparrow has gotten to be the bird with the largest range not simply due to its introduction in different habitats. It is the adaptability and flexibility of this bird that has made it so successful. Sparrows are inventive in how they forage for food (they are willing to explore food sources before other birds) and even in how they build their nests (in cities sparrow nests can be found with cigarette butts, which help repel parasites). I admit that this chapter gave me a bit more respect for the bird that always seem to monopolize the seed in my bird feeders. Now I can appreciate why!

Pigeon brain via Wikimedia Commons

I also enjoyed learning more about how researchers figure out how bird brains work. (Hint: it isn't just about dissecting them!) My favorite chapter involved understanding the navigational systems of birds. Thanks to experiments with birds that are superstars for their ability to navigate, including homing pigeons and an array of migratory birds, scientists have learned that birds use a two step "map-and-compass strategy. Like so much of neuroscience, they figured this out by knocking out one sense and seeing if homing pigeons could still get home. The compass seems to rely on magnetoreceptors near the beak, but the map strategy is not as clear. The theory now goes that birds create extensive maps of where they have stored caches of food or where they need to return to nest.
Birds that excel at navigation have a larger hippocampus, the region of the brain that stores maps and memories; what's more this brain region can get bigger just by using it more. This correlation was also observed in a study of London cab drivers, where drivers with a longer work history have a correspondingly bigger hippocampus.

As you can tell, the book is filled with tons of interesting examples of bird behavior and neuroscience. One high point was the fascinating history of the homing pigeon, which has been used by Julius Caesar, Allied troops in North Africa, and modern day Cuban military officials. (I can't believe this hasn't been its own book.) In short, I recommend The Genius of Birds, especially if you you have an interest in birds, animal behavior, or the brain.