Tuesday, December 17, 2019

Secret Science Club Post-Lecture Recap: A Whale of a Subject

Last night, I headed down the the beautiful Bell House, in the Gowanus section of Brooklyn, for this month's Secret Science Club. This month's lecture featured the triumphant return of Dr David Gruber, marine biologist and adventurer of Baruch College at the City University of New York and CUNY Graduate Center, the American Museum of Natural History, and the National Geographic society. Dr Gruber's first appearance at a SSC event was in January 2009 (sadly before the advent of this blog) when he appeared as a guest of neuroscientist Dr Vincent Pieribone. His second appearance for the SSC was in July 2014, when the good doctor headlined a lecture about biofluorescent marine organisms.

Dr Gruber's lecture was titled The 'Aliens' Beneath the Waves, an apt title for a discussion of some gloriously strange denizens of the deep. He jokingly referred to himself (being an expert of marine biofluorescence) as the 'Glowing Guy' and stated that he had a goal to travel to the top of the world, where it is dark for half of the year. This entailed a year of dry-suit SCUBA diving, after which he was still miserable in the Arctic, continually asking himself, "Was this a good idea?" He jokingly detailed a couple of his bad ideas, such as a one-person submersible which had a tendency to spin and a swim with sharks during which he tested the use of a hockey helmet as protection. He traveled to Greenland with a small crew from the American Museum of Natural History, among them curator of ichthyology Dr John Sparks. Before their expedition, there were only about three-hundred Arctic fish species described. While Dr Gruber went to Greenland to find adventure, he found a dripping mess, much like 'an icebox left open'. He described the powerful experience of seeing the melting of Greenland firsthand. Dr Gruber displayed the neologism 'solastalgia', coined to describe the cumulative impact of climatic and environmental change on mental, emotional, and spiritual health. He stated that he didn't like the concept because it conveys a feeling of despair which can prevent humans from realizing that we can change our current course.

Dr Gruber then described a course of study that he recently embarked upon, a study to determine if we can learn to communicate with sperm whales (Physeter macrocephalus). We are not alone on the planet... how can we break the interspecies communication barrier as a means of connecting to nature? He half-jokingly said that learning to communicate with sperm whales could one day be a springboard to communicating with aliens.

Sperm whales are deep divers. Trained human free-divers are able to hold their breath for approximately five minutes- Dr Gruber quipped that we should recruit athletes as scientists, a cadre of mermaids and mermen to explore the deeps. Sperm whales can dive to a depth of one-and-a-half miles on a single breath, remaining underwater for about two hours, then resting for five or six minutes. The have the largest known mammalian brains, weighing up to eighteen pounds. They communicate in rhythmic social 'codas' (different dialects exist among diverse populations)- patterns of broadband clicks. They also use these clicks for an echolocation more sensitive than human-designed sonar. It's possible that they communicate by forming three-dimensional sound 'images' analogous to holograms.

Whales evolved from artiodactyls, even-toed hoofed mammals. Their terrestrial ancestors most likely resembled hippos. They have had a long time to evolve to their current marine environment- among modern whales, the Odontocetes (toothed whales) split from the Mysticetes (baleen whales) about 34 million years ago. Put succinctly, sperm whales are ancient. Dr Gruber waxed lyrical about looking a whale in the eye, and noting that curiosity is apparent.

Dr Gruber's foray into cetology began two years ago, when he participated in a fellowship at Harvard. He arrived known as 'the Jellyfish Guy'. During this fellowship, Dr Gruber played a whale song to a cryptographer, ho asked him how many whale sounds he had, then invited him to a machine learning group. Sperm whales produce sound with organs known as monkey lips and the vast reserve of spermaceti oil and waxes in their heads focus the sounds. Besides the series of clicks known as codas, sperm whales also produce sounds known as creaks and trumpets. Sometimes the whales touch their jaws together to allow bone-to-bone communication.

Among the machine learning group, Dr Gruber, playing his whale songs, joked that he felt like a kid playing with Tonka trucks, but the machine learning experts were hooked as they analyzed the spectrograms. They wanted to know which whale expert had the largest data set of whale songs. and contacted Dr Shane Gero of the Dominica Sperm Whale Project. The collaboration resulted in a paper: Deep Machine Learning Techniques for the Detection and Classification of Sperm Whale Bioacoustics. Dr Gruber was faced with the challenge: what do we do with this? He convened a two day conference with scientists from many disciplines to study the subject, and somewhat sheepishly rattled off the tongue-twister of a name of the conference: Novel Ways to Non-invasively Visualize/Characterize/Decipher the Sonic Communication of Marine Mammals, Particularly Sperm Whales (Physeter macrocephalus), via Compact, Low-noise, High-resolution Underwater Devices.

Dr Gruber averred that we can do this, we will be able to communicate with whales. He rattled off some interesting topics to explore- do whales talk about the past? He likened the development of communication with whales to Jane Goodall's discovery of tool use among chimpanzees in terms of game-changing discoveries.

One of the main results of the conference would be the development of non-invasive swimming robots that could track whales and conduct breath analysis of whales. There are about 300,000 sperm whales in the planet's oceans. Whale tags must be improved, with non-invasive designs developed- one tag design is patterned after remoras. One difficulty in studying whale communications is the 'cocktail party problem'- how do we distinguish communications? An integration of visual and acoustic data must be obtained from an array of microphones and cameras to figure out what is being communicated.

Dr Gruber then gave a quick 'how did I get here?' narrative. Most of his work in the field of animal communications involved fluorescence in marine life- animals take in blue light and employ it in secret channels of communication, revealed through the use of special equipment. He began this portion of the lecture by showing us video of the first fluorescent Arctic fish found. He then displayed some lovely footage of tiny flashlight fish (Anomalops katoptron) in the Solomon Islands:

He positively rhapsodized about the schooling behavior of these tiny fish, quipping that they formed a sort of 'blue brick road' as they swam in formation. He described them as 'the weirdos of the fish world', noting that they have highly vascularized sacs under their eyes in which they nourish the bioluminescent bacteria which provide their light. The fish flee from artificial light, so super-sophisticated cameras are needed to film them- a 64,000 light intensity camera was used to video them from a distance. The underwater ballet of these fish is collective behavior, as ad hoc leaders school in darkness. Dr Gruber hypothesized that the deep sea might be filled with schooling fish which flee the lights of submersibles.

Fluorescence was also found in the swell shark (Cephaloscyllium ventriosum), formerly thought of as an uninteresting little shark. The sharks exhibit sexual dimorphism in their fluorescent patterns, with females having 'masks' clustered around their faces:

To understand how the sharks perceive their world, Dr Gruber brought shark specimens to an eye doctor, who discovered that the sharks only have one pigment in the cone cells of their eyes, while humans have RGB pigments. Dr Gruber had to design a camera which filtered out wavelengths in order to mimic the sharks' eyes.

Dr Gruber also discovered fluorescence in a hawksbill sea turtle (Eretmochelys imbricata):

Dr Gruber showed an uproariously funny video (which I haven't tracked down online) of himself testing the vision of a turtle by flashing a color chart at it, joking, "This is as nerdy as SCUBA diving gets!" In order to figure out the perception of a turtle, he employed a hyperspectral satellite camera which can hold a lot of data... while it has broad color. Sea turtle eyes have drops of oil in their cone cells which help them to perceive fluorescence. Dr Gruber then showed us mock-ups of vision charts for various organisms, with humans having poor low-light vision while sharks have poor distance vision, but an acute sense for detecting motion.

Dr Gruber quipped that some of his work isn't glamorous, such as scooping dirty water out of a canal in Mystic, CT in order to study Ctenophores, or comb jellies, which are gelatinous plankton. Ctenophores are studied primarily because they can show us of how neurons evolved. In order to study animals such as ctenophores, Dr Gruber wanted to develop gentle robots in order to collect them without harming them. Dr Gruber noted, "We create the future, we don't need to kill animals in order to study them." A gentle robot which exerts one-tenth of the pressure of a human eyelid was developed to study jellyfish, and it can also be repurposed to pick strawberries without bruising them. Use of this robot didn't stress the jellyfish and initiate self-repair responses. Another design was inspired by origami, it folds to encase specimens... Dr Gruber joked that it was a 'spa treatment' for organisms, which could be studied physiologically and scanned to create three-dimensional models. Again, Dr Gruber stated that there is no need to kill animal specimens, and made the case for a super-intentional future: we make the future, and we can determine what sort of artificial intelligence we create. "There's no need for killers", he joked, "Soft robots will only kill a few people." He then displayed video of a glove which can be used to control a submersible's robotic arm... a 'squishy' robot arm. This human extension will allow interaction between researchers and marine life.

The displays of fluorescent marine life continued, with images of pyrosomes (chordates, they are distant relatives of ours) and box jellyfish ('the rockstars of the jellyfish world', with 24 eyes of 4 varieties and a venom which packs a whallop).

After this long digression about his 'origin story' as an animal communication researcher, Dr Gruber then returned to the subject
of whales, citing Roger and Katie Payne's recordings of humpback whales as an inspiration. Whale songs have been recorded since the 1950s after naval hydrophones picked them up. Returning to the sperm whale, Dr Gruber noted that they live in matriarchal societies, with males leaving their birth pods but often returning up to fifteen years later. He displayed a diagram of the two-hundred and fifty pound heart of a sperm whale and described it as 'a linebacker of a heart'. Having a big heart himself, he finished his lecture by stating, in the face of a Sixth Extinction, we can change course.

The lecture was followed by a Q&A session. The first question involved the use of Green Fluorescent Protein in neurological research, which was covered in his 2014 lecture. There are eels with bilirubin-binding fluorescent proteins and sharks with tryptophan-derived fluorescence. Regarding fluorescent sea turtles, out of the seven extant species, only the leatherback turtle doesn't exhibit fluorescence. With regards to the B-52 Whale or Lonely Whale, which was picked up by a Navy hydrophone, while it may be a specimen of a exceedingly rare whale, it might just be a 'bad singer', using a different frequency than its compatriots.

Regarding the development of gentler collection techniques, Dr Gruber noted that scientists generally have a low impact on marine populations, but that they must set examples for others- he confessed, "I have fish blood on my hands." A question about the original notation of sperm whale recordings, Dr Gruber stated that it was done by hand, using recordings of the small population of well-known sperm whales off Dominica. There were questions regarding 'conversations' that whales might engage in... how do adults and infants commnicate? Do whales employ subterfuge? Dr Gruber joked that he had a nightmare that all the whales were swearing all the time, "That whale is a jerk!" He noted that communicating with whales, and figuring out their communications, has to get better than what we are doing now. This has to be a deep listening project, without some of the ethical lapses former researchers engaged in back in the 'dark days of whale research' which involved LSD and less savory... uhhh... stuff.

Some bastard in the audience asked about the differences in sound-producing anatomy between the baleen whales and the sperm whale in particular. Baleen whales echolocate and their songs are probably involved in mating rituals. Sperm whales, however, are so weird, so different from baleen whales and dolphins that it is hard to compare them. The closest relatives they have among the cetaceans is the pygmy sperm whale (Kogia breviceps), but they are relatively distant relations.

I often talk about the 'Secret Science Sweet Spot' when I write the lecture recaps, and I have to say that Dr Gruber hit on all cylinders. His lecture was that perfect blend of hard science, adventure narrative, and advocacy, leavened with humor and illustrated by glorious photographs and video. Dr Gruber also conveyed a sense of optimism which I sometimes find lacking in myself- his avowal 'WE MAKE THE FUTURE' was a much-needed rallying cry. I actually thanked him for his optimism after the lecture. Also, this was Dr Gruber's third Secret Science Club lecture, each delivered in five year intervals... it was delightful to see his career trajectory in these three lectures. His first appearance on the SSC stage was as a young scientist speaking as an adjunct to a senior colleague. His second lecture was about a very specific topic, a course of study which cemented his reputation not only as a scientist, but as an explorer. This third lecture was that of a 'mature' researcher, engaged in a wide-ranging project involving colleagues from many disciplines. Put in gaming terms, each lecture represented a levelling-up. I'm a bio guy, and I've been privileged to attend these three lectures at three stages of Dr Gruber's career, and I have to say that this was one of the best Secret Science Club lectures of all. Kudos to Dr Gruber, Dorian and Margaret, and the staff of the beautiful Bell House.

While I haven't found any long video which would pertain to the main subject of this lecture, Dr Gruber has a lot of videos featuring specatacular imagery. Pour yourself a nice, refreshing beverage, and bask in the glory of SCIENCE!

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