Mozambique Diary: A single breath that changed the planet

The sound of an early ancestor of this lungfish (Protopterus annectens) taking it first gulp of air signified a pivotal moment in the history of life on Earth. The emergence of this behavior, along with the development of four limbs, set the stage for the conquest of terrestrial habitats by vertebrates, and the evolution of all tetrapods.

The sound of an early ancestor of this lungfish (Protopterus annectens) taking its first gulp of air signified a pivotal moment in the history of life on Earth. The emergence of this behavior, along with the development of four limbs, set the stage for the conquest of terrestrial habitats by vertebrates, and the evolution of all tetrapods.

About 400 million years ago, in the Devonian, in what was likely a shallow, freshwater pond in some tropical part of the world, a fish made a sound that started a dramatic chain of events, one that culminated in you and me being born. The sound was that of air being sucked in, as the fish lifted its mouth above the surface of the water, desperate to replenish falling oxygen levels in its bloodstream. Soon, gulping for fresh air became a necessity, as the gills failed to supply enough oxygen from the warm, muddy waters to sustain the animal’s activity. Its bladder, which up to that point helped maintain buoyancy for swimming, started to function as a gas exchange organ, an early version of lungs. At the same time, the fish’s pelvic and pectoral fins grew sturdier, and their connection to the rest of the skeleton more capable of lifting the body above the substrate. With these two steps the stage for the vertebrate conquest of land was set. We probably will never know when and where exactly this momentous transition took place, but we are pretty sure of what that fish looked like. And I am staring at it right now, as it looks back at me from the bottom of my beer cooler.

The Southern African lungfish (Protopterus annectens brieni)

The Southern African lungfish (Protopterus annectens)

Ever since I first set foot in Gorongosa National Park in Mozambique I have been obsessed with meeting my oldest living vertebrate cousin, the lungfish (Protopterus annectens). Despite its unassuming physique, reminiscent of a large eel, the lungfish holds a special place in the history of life on Earth. Biologists have always suspected that the lungfish gave us insight into the origin of terrestrial vertebrates, but only last year a massive molecular phylogenetic analysis (pdf) , based on 251 (!) genes, proved that the lungfish is a sister taxon to all tetrapods – amphibians, reptiles, birds, and you, and the rest of mammals. Previously that place was reserved for the coelacanth, a marine fish of equally ancient provenance, but now it appears that the coelacanth is an earlier offshoot of fishes that went its own, equally interesting, if less pivotal, way.

My first encounter with the lungfish took place a couple of months ago, when I ran across a fisherman who had caught a couple of these animals. Alas, by the time I met him they had been killed and gutted, leaving me heartbroken and even more obsessed. This time I made it abundantly clear to anybody who would listen that I wanted a live lungfish, and last week a fisherman from the village of Vinho finally delivered one into my hands.

In Gorongosa National Park lungfish are common, if rarely seen, inhabitants of seasonal water pans. During the dry season, when the pans evaporate, the lungfish burry themselves in the mud and estivate for several months. During this period their metabolic rates drop by about 60% and gas exchange is done entirely through their lungs.

In Gorongosa National Park lungfish are common, if rarely seen, inhabitants of seasonal water pans. During the dry season, when the pans evaporate, the lungfish burry themselves in the mud and estivate for several months. During this period their metabolic rates drop by about 60% and gas exchange is done entirely through their lungs.

It is difficult to describe the nearly religious reverence I felt when I saw my first live lungfish. Here was an animal that, I am pretty sure, looked like something I would see in the ponds of the early Paleozoic, long before first amphibians, even longer before dinosaurs. As I watched the lungfish slowly moving in my cooler, it suddenly lifted its head above the water and loudly inhaled a big gulp of air. I don’t think I will ever be able to forget the sound of it.

The lungfish does not have fins like other fishes. Rather, it has two pairs of whip-like appendages that act as weak, but very much functional legs. In 2011 an interesting experimental study (pdf) demonstrated that the pelvic fins are used by the lungfish in a fashion very similar to that of the land animals’ hind legs, for both walking and bounding. This in turn casts a new light on some early Devonian fossil tracks that were thought to have been left by primitive amphibians – in fact, they probably are those of semi-terrestrial lungfish ancestors. The development of articulated limbs with fingers (digited limbs) no longer seems to be the prerequisite to the conquest of land.

If you think that this looks like walking that’s because it is. Lungfish use their pelvic fins in a way very similar to that of a tetrapod’s legs – the distal part of the fin becomes a “foot” and the fins produce both walking and bounding motions.

If you think that this looks like walking that’s because it is. Lungfish use their pelvic fins in a way very similar to that of a tetrapod’s legs – the distal part of the fin becomes a “foot” and the fins produce both walking and bounding motions.

The more we study the lungfish the more fascinating it becomes. It is now clear that this animal holds the secret to the development of tetrapod ears, and they were the first to develop enameled teeth, the kind we, mammals now have. The lungfish is also superbly adapted to the harsh seasons of the southern African savanna, and can burry itself in the ground and survive for months out of water, hidden from the hot sun in a muddy cocoon (stories abound about African farmers digging out live, large fish from their dry fields.) Its dependence on atmospheric oxygen is so strong that the lungfish will drown if not allowed to breathe above the surface of the water. Its strongly reduced gills are virtually non-functional, but during the lungfish’s larval development are external and feathery, resembling those of the salamander larvae.

A portrait of the Southern African lungfish (Protopterus annectens brieni) from Gorongosa.

A portrait of the Southern African lungfish (Protopterus annectens) from Gorongosa.

In Gorongosa lungfish are common in seasonal pans and rivers of the park, feeding on a wide range of aquatic invertebrates, smaller fish, and frogs. As they are highly territorial, it is likely that almost every body of water on the plains has at least one of these remarkable animal. It is a shame that they are never seen by the visitors to the park – in my opinion the lungfish surpasses in its importance and a fantastical set of features any other vertebrate of Gorongosa, lions and elephants included, and I vow to make it my mission to spread the knowledge of its existence.

Last week, on March 27th, the E.O. Wilson Biodiversity Laboratory was officially opened, a culmination of my and many other people’s dream. More about the Laboratory soon, but I thought it fitting that the first vertebrate sample for our synoptic collection is a small snippet of the lungfish’s caudal fin, preserved for future DNA barcoding. The animal itself is being released back into its habitat, and I hope that this was not the last time that I looked into the eyes of my grand…grandfather’s twin brother.

Resembling an oversized salamander, the lungfish has four distinct limbs, a long tail, and only remnants of gills. The gills are virtually non-functional and the fish will drown if not allowed to breathe above the surface of the water.

Resembling an oversized salamander, the lungfish has four distinct limbs, a long tail, and only remnants of gills. The gills are virtually non-functional and the fish will drown if not allowed to breathe above the surface of the water.

BugShot 2014: Sapelo Island, GA

Polyrhachis

Intimate portraits: A queen ant (Polyrhachis armata)

My arrival in Johannesburg has brought a welcome respite from the unbearable winter of New England, and tomorrow I fly to Gorongosa National Park to begin preparations for the official opening of the E.O. Wilson Biodiversity Laboratory on March 27th. Stay tuned for updates and photos!

But there is something else that I am very excited about. Last year I was invited by Alex Wild to teach an insect photography workshop in Belize, the famous BugShot, and this year we are doing it again. This time the workshop will take place on Sapelo Island in Georgia, a place I have never been to but always wanted to visit. Insect life is bound to be spectacular – among other things I expect to find there Brunneria borealis, North America’s largest praying mantis and the world’s only fully parthenogenetic species of these insects. There are webspinners (Embioptera) there, two species of sylvan katydids (Pseudophyllinae), and over 100 species of other orthopterans. This is going to be good.

High-speed macrophotography: Periodical cicada (Magicicada septendecim)

High-speed macrophotography: Periodical cicada (Magicicada septendecim)

The workshop will take place on May 22-25 and there are still a few empty slots left. If you want to learn macrophotography, perfect your technique or learn a new one, or simply find out amazing facts about invertebrates, then you should join entomologists and photography experts Alex Wild, John Abbott, and myself on this fun adventure. Visit the BugShot website to find more details.

Wide-angle macro: Sylvan katydid (Celidophylla albiomacula)

Wide-angle macro: Sylvan katydid (Celidophylla albiomacula)

Time lapse macrophotography: A molting katydid (Enyaliopsis petersi)

Time lapse macrophotography: A molting katydid (Enyaliopsis petersi)

Ambient light macrophotography: Atlantic shield-back (Atlanticus testaceus)

Ambient light macrophotography: Atlantic shield-back (Atlanticus testaceus)

Tough as nails

Vernal pools are unique aquatic ecosystems, fleeting and unpredictable, but rich in animal life.

Vernal pools are unique aquatic ecosystems, fleeting and unpredictable, but rich in animal life.

Last night I finally managed to see the movie “Gravity”, which proves to me incontrovertibly that humans are not meant to stick their noses outside the protective layer of Earth’s atmosphere, despite having developed all kinds of high tech space gear (which, incidentally, seemed to have been designed primarily to kill Sandra Bullock’s character.) But this unexpectedly beautiful movie also made me think of a certain creature, whose amazing survival skills had lead NASA to use it to test the limits of life’s perseverance in outer space, long before somebody finally realized that people floating aimlessly in the cosmic void make for much better television.

To photograph fairy shrimp and other inhabitants of vernal pools directly in their habitat I used a complicated underwater setup with live video feed that allowed me to see what was in front of the lens. When I turned it on I was amazed how much life was there, it was almost as if I suddenly looked at a tiny coral reef.

To photograph fairy shrimp and other inhabitants of vernal pools directly in their habitat I used a complicated underwater setup with live video feed that allowed me to see what was in front of the lens. When I turned it on I was amazed how much life was there, it was almost as if I suddenly looked at a tiny coral reef.

As the first sunny days of March begin to melt away frozen remainders of winter in the northeaster United States, members of an ancient lineage of animals are getting ready to spring back to life. Throughout most of the year their habitat was as dry as a bone, but when the last patches of snow turned into water, leaf-packed depressions on the forest floor suddenly transformed into small, ephemeral ponds. Known as vernal pools, these fleeting bodies of water will be gone again by the time summer comes, but for now they create a unique aquatic ecosystem. Soon, the water is filled with thousands of tiny animals, at first not much larger than the point at the end of this sentence, but within a few weeks reaching the length of nearly a half of a pinky finger. They are the fairy shrimp (Eubranchipus vernalis), members of a group of crustaceans known as branchiopods, animals that were already present in the Cambrian seas half a billion years ago, before any plants even considered leaving water for terrestrial habitats.

Male fairy shrimp have massive, highly modified antennae, which they use to grasp and hold the female during mating.

Male fairy shrimp (Eubranchipus vernalis) have massive, highly modified antennae, which they use to grasp and hold the female during mating.

Looking at the delicate, soft body of a fairy shrimp it is hard to imagine how a lineage of organisms so seemingly fragile could have survived for so long. Take one out of the water, and it is dead within seconds. Let the oxygen level in the pond drop, and the entire population is wiped out. Given a chance, a single fish could probably do away with them all in a day, but luckily fish don’t do well in ponds that last for only a few months of a year. But fairy shrimps’ frailty is an illusion because where it counts they are as tough as nails.

In the northeastern United States several species of salamanders, such as this Spotted salamander (Ambystoma maculatum) from Westfield MA, share vernal pools with the fairy shrimp.

In the northeastern United States several species of salamanders, such as this Spotted salamander (Ambystoma maculatum) from Westfield MA, share vernal pools with the fairy shrimp.

If you live in a place as transient as a vernal pool, here now but gone in a few months, an environment of unpredictable duration and often uncertain arrival, you better have a solid survival strategy to build your life around. First, once the right environment appears, you must develop very quickly and reach reproductive maturity before the changing conditions kill you. Second, you need a method to keep your genetic line alive, even when the only habitat in which you can survive is gone. And third, plan for the unforeseeable cataclysms, such as sudden evaporation of the pool before you are ready to produce a new generation. Because, if you fail on any of these accounts, your species will not last past the first generation. Fairy shrimp, despite their unassuming physique, are master survivalists in the most hostile and unstable of habitats, and execute the three-step action plan flawlessly.

Male fairy shrimp (Eubanchipus vernalis).

Male fairy shrimp (Eubanchipus vernalis) from Estabrook Woods, MA.

As soon as the vernal pool forms, cysts containing fully formed shrimp embryos from the year before break open, and minute, swimming larvae emerge. They immediately start feeding on microscopic algae and bacteria already present in the water, and grow like crazy. During the first few days of their lives, baby fairy shrimp, known as nauplii, increase their length by a third and nearly double their weight every day. In about a month the animals are fully grown. One pair of the males’ antennae develops into giant, antler-like projections that help them catch and grasp their mating partners, while females grow big egg pouches on their abdomens. A few days later females start to lay at the bottom of the pool large clutches of cysts, eggs with embryos already developing inside, and die shortly after. Soon the water level in the pool begins to drop, and by June all traces of the once vibrant aquatic habitat are usually gone.

The body of a fairy shrimp is nearly translucent, which makes them invisible to a predator looking from above.

The body of a fairy shrimp is nearly translucent, which makes them invisible to a predator looking from above.

But inside the cysts hidden under a thin layer of soil the embryos are very much alive. They slowly continue their development, but can remain in the dormant state, out of the water, baking in the sun or being frozen in ice, for many years. Their outer shell is nearly waterproof, and quite sticky. This stickiness explains the sudden appearance of fairy shrimp in the most unexpected places, including old tires filled with water, after hitching a ride on the legs of birds and other animals. These cysts can live through being dipped in boiling water and liquid air (-194.35 °C, or -317.83°F), which is one of the reasons why these organisms are being used by NASA to test the survival of life outside of Earth’s atmosphere.
The following spring, if everything goes as planned, water of the melting snow awakens the dormant embryos, and within a few days they break the shell of their tiny survival capsules. But not all of them. Only a portion of the cysts responds to the first appearance of water, while others continue their slumber. If the pool dries prematurely, as it sometimes happens during a particularly warm spring, all early hatchlings die, and a second batch of larvae will emerge only if the pool fills up with water again. It has been shown that some cysts in a clutch will wait through eight cycles of wetting and drying before finally deciding to hatch. Fairy shrimp have evolved this ingenious strategy of hedging their reproductive bets in response to the erratic nature of their habitat, and it clearly serves them very well.

Fairy shrimp swim upside down, using 10 pairs of legs to propel themselves and collect bits of algae to feed on.

Fairy shrimp swim upside down, using 10 pairs of legs to propel themselves and collect bits of algae to feed on.

Mozambique Diary: Pardalota

Pardalota reimeri, probably the most colorful and one of the rarest katydids in the world. The individuals I observed in Quirimbas are the first record of this species in 103 years.

Pardalota reimeri, probably the most colorful and one of the rarest katydids in the world. The individuals I observed in Quirimbas are the first record of this species in 103 years.

Ever since I can remember I have been having a recurring nightmare: I am in some incredible location – usually somewhere in the tropics, there are amazing insects everywhere, often those that I have been dying to find, but I need to leave immediately and have none of my collecting gear – not a single vial, no net, no camera (not everybody can relate, I realize, but entomologists know what I am talking about). And last month I finally got to live through this bad dream.

A defensive display of Pardalota reimeri – these katydids feed on highly toxic plants and is likely that their bodies are loaded with poisonous alkaloids.

A defensive display of Pardalota reimeri – these katydids feed on highly toxic plants and is likely that their bodies are loaded with poisonous alkaloids.

Before coming to Gorongosa I flew to the northern town of Pemba where a newly opened campus of the University of Lurió trains Mozambican students in biology and engineering. It was supposed to be a strictly-business trip, meeting lecturers and students, and for this reason I did not bring with me any collecting or sound recording equipment, and only the most basic photo gear. But my friend Harith had a better idea and decided to take me on a short trip to Quirimbas National Park, famous chiefly for its spectacular marine life. Some of his students were working on insect and amphibian faunas of the park, and I said, “Why the hell not.” The seemingly easy trip turned briefly into hell after our Mitsubishi truck decided to part ways with its clutch right in the middle of nowhere. After a long while a friendly driver in a passing car went to fetch a tow truck for us, and eventually we made it to the park.

An unidentified, aposemtically-colored tiger moth found on the same plants as Pardalota.

An unidentified, aposemtically-colored tiger moth found on the same plants as Pardalota.

The first thing that I noticed was the wall of insect sound. The lush miombo forest reverberated with loud katydid calls, ones that I did not recognize. They were unusual for a couple of reasons. One, it was the middle of a hot, African day, and katydids tend not to like it, preferring to call under the cover of the night. And two, the calls were continuous, low frequency, and very complex. They were telling everybody with ears, “Here I am, come and get me.” And when you do that you better have a good trick up your sleeve to protect yourself, as katydid ladies are not the only ones listening: birds, lizards, monkeys, they all love big, juicy insects.

The katydids were calling from high in the trees and I was afraid that I would not be able to catch, or even see them. But then one flew down from the canopy and landed right in front of me. When I saw what it was, my heart skipped a beat – it was Pardalota reimeri, the Holy Grail for katydid aficionados (there are a few of us out there). This species had been known only from the original type series, described in 1911 and preserved in a museum in Berlin. What is special about this species is that even those old, dried husks retained vivid, crazy colors, unlike those of any other known katydid species. And colors as awesome as this indicate an equally awesome biology.

I caught the katydid and he immediately went into a defensive mode: he opened his bright purple, black and white wings, and exposed his neon-orange abdomen and cervical membrane; he lifted his hind legs that had yellow and black markings, remarkably similar to those of toxic chrysomelid beetles. This was either a daring bluff, or this thing was seriously poisonous. All around me other males continued to sing.

A video of a P. reimeri nymph – although the insect is not feeding it gives the perfect illusion of the front end of a fuzzy caterpillar chewing on a leaf.

What to do? Here I was, surrounded by a remarkable entomological discovery, but with no way to collect, preserve, or record it. I decided to exploit Harith’s students and we fanned out looking for the insects. Soon we discovered where they sang – they were only calling from, and feeding on, two species of trees, both known to produce potent chemical defenses, including some powerful psychoactive alkaloids. This almost certainly explained their aposematic coloration. We also found nymphs of this species, which turned out to be incredibly hairy. In fact, when I first saw one I thought I was looking at a fuzzy caterpillar feeding on a toxic plant – its movements were an uncanny imitation of the front end of a caterpillar chewing on a leaf, even though I was looking at at the katydid’s butt. It wasn’t shocking then when a minute later I noticed very similar looking caterpillars feeding on the same plant and, also on the same plant, tiger moths (well known to be toxic) wearing colors very similar to those of the katydids’. Having nothing else at my disposal I pointed my Canon 6D at the canopy and used its video recording feature to record the sound of the singing males. I collected as many individuals as I could, stuffing them into Ziplock bags, hoping to be able to get decent photos and proper sound recordings later on.

In the end I managed to collect enough material and data to write a short note about the biology of this species. But not being able to do a very good job at data and specimen collecting in the field was not a pleasant experience. I have already learned never to go anywhere without my headlamp, a GPS, and a camera, and now I am adding to this list an ultrasonic sound recorder and a large set of vials with 96% ethanol. On the second thought, maybe also an extra clutch for a Mitsubishi and a satellite phone. And some beer, for emergencies.
Two nights later I had a nightmare about Quirimbas.

A female P. reimeri cleaning her foot.

A female P. reimeri cleaning her foot.

Mozambique Diary: Sibylla

A portrait of the Precious Sibyl mantis (Sibylla pretiosa) – it is easy to get the impression that this insect really thinks.

A portrait of the Precious Sibyl mantis (Sibylla pretiosa) – it is easy to get the impression that this insect really thinks.

These days, if God speaks directly to you, be it about the precise date for the end of the world or his opinion about somebody else’s sexual preferences, you are either a crazy nut or a Westboro Baptist crazier nut. Ancient Greeks, clearly more open minded about such things, referred to a woman with powers to prophesy God’s actions with a much nicer-sounding honorific – Sibyl. Perhaps the 19th century Swedish entomologist C. Stål saw some of that craziness in the facial features of a gracile praying mantis from southern Africa, and christened it Sibylla pretiosa – the Precious Sibyl. Looking at this remarkably anthropomorphic insect it is indeed easy to get the impression that some strange thoughts are percolating in its brain.

The Precious Sibyl mantids (Sibylla pretiosa) are usually found high on the branches of savanna trees.

The Precious Sibyl mantids (Sibylla pretiosa) are usually found high on the branches of savanna trees.

I first encountered Sibylla many years ago in Zimbabwe, amazed at the sight of large mantids, nearly ghost-like in their slender built and pale coloration, that were zipping up and down smooth tree trunks. Last year I once again found Sibylla while collecting insects high in the canopy of a large Combretum tree in Gorongosa National Park. Alas, it was a tiny nymph. This month, however, while in Gorongosa during the peak of the rainy season, Sibyllas were plentiful on tree trunks and at the lights of the Chitengo Camp.

A male Sibylla cleaning his antennae.

A male Sibylla cleaning his antennae.

Despite their fragile appearance, these insects are skilled hunters, capable of catching and devouring prey at least half as long and nearly as heavy as themselves. They slowly stalk crickets and moths found on the bark, constantly vibrating their antennae in a fashion similar to that in many parasitoid wasps, which may indicate the use of chemical signals in detection of their prey. I have also seen these mantids feeding at night, which further supports the possibility of using non-visual cues while hunting.

Young Sibylla are very spindly looking and are found usually on leaves and tips of thin branches.

Young Sibylla are very spindly looking and are found usually on leaves and tips of thin branches.

Although superficially similar to empusid mantids, Sibylla is more closely related to another amazing dead leaf mimic, the Ghost mantis (Phyllocrania paradoxa), which I yet need to find in Gorongosa (but I was told by a resident that he had seen one). Most of the 14 known species of the genus Sibylla are found in West and Central Africa, and the individuals from Gorongosa are the first records of this genus of insects in Mozambique.

Sibylla mantids are closely related to the otherworldly Ghost mantids (Phyllocrania paradoxa). I have not yet found one in Gorongosa, but I am pretty sure that we have them there.

Sibylla mantids are closely related to the otherworldly Ghost mantids (Phyllocrania paradoxa). I have not yet found one in Gorongosa, but I am pretty sure that we have them there.

Alas, having caught quite a few individuals of Sibylla attracted to my mercury vapor lamp in Gorongosa, I am now convinced that this pretty insect does not have the powers to foretell the future. Otherwise they would have known that if you come to my light, you never leave.

Sibylla are voracious predators of insects found on tree bark and branches.

Sibylla mantids are voracious predators of insects found on tree bark and branches.

Mozambique Diary: Blind snakes of Gorongosa

A comparison of the largest blind snake of Gorongosa, the Giant blind snake (Megatyphlops schlegelii), and the smallest one, the Peter's thread snake (Leptotyphlops scutifrons)

A comparison of the largest blind snake of Gorongosa, the Giant blind snake (Megatyphlops schlegelii), and the smallest one, the Peter’s thread snake (Leptotyphlops scutifrons)

Last night’s downpour flushed out a lot of things from under the ground, and one of them was a large blind snake, Megatyphlops schlegelii, which I found as it was swimming in a puddle in front of the Scientific Services’ trailer. Now, large is a relative term – the snake is only a little over a foot long and as thick as a finger, but for blind snakes this is huuuge. Blind snakes, families Typhlopidae and Leptotyphlopidae, comprise some of the smallest reptiles, and definitely the smallest snakes, in the world. In fact, one species, Ramphotyphlops braminus, has spread over the globe with potted plants, mistaken for a small earthworm in the soil.

Both families are considered some of the most basal lineages of snakes, which means that their morphology and behavior gives us some insight into how snakes evolved from their closest relatives, lizards (or, more specifically, clade Toxicofera, which includes monitor lizards, agamas, and a few other groups). They are all subterranean and their morphology reflects this fact in the small but massively calcified skull, hard “beak” made of thick scales that allows them to push through the soil, and incredibly smooth body that minimizes frictions as they tunnel underground. The eyes are vestigial, hidden under semi-translucent scales, and are visible only as darker, light-sensitive spots on the sides of the head. Unlike other snakes they also lack a distinct tail – the body pretty much ends in a cloaca and all that remains of the tail is a tiny, sharp spike, their only defensive weapon.

The morphology of the Giant blind snake (Megatyphlops schlegelii) reveals its perfect adaptation for subterranean life – there is no neck or distinct tail, which means that the animal can move as easily forward as backward in the underground tunnels; notice the sharp defensive spike on the end of the body.

The morphology of the Giant blind snake (Megatyphlops schlegelii) reveals its perfect adaptation for subterranean life – there is no neck or distinct tail, which means that the animal can move as easily forward as backward in the underground tunnels; notice the sharp defensive spike at the end of the body.

Needles to say, blind snakes are completely harmless. They produce no venom and may even lack teeth in either the upper or lower jaw. When caught they try to jab the attacker with the tip of the tail, which is about as effective a defense as being licked by a puppy. Still, the first Megatyphlops I saw in Gorongosa was an animal being hacked to bits by villagers afraid of its (imaginary) venom.

The body of blind snakes is glossy smooth, reducing friction when moving underground. It also makes holding them in your hand rather difficult.

The body of blind snakes is glossy smooth, reducing friction when moving underground. It also makes holding them in your hand rather difficult.

So far I have found three species of blind snakes in the park, usually while flipping rocks when looking for crickets. Interestingly, I have also seen them frequently on the surface at night, moving slowly and deliberately, as if looking for something. These snakes feed mostly on termites and ants, the nests of which are often located under rocks and logs. I imagine that it is easier for the snakes to move on the surface to the next rock, than to plow under the surface, which may explain their behavior. Some blind snakes are known to produce pheromones that mimic those of their prey, thus protecting them from attacks by soldier termites and ants. Their feeding mechanism is different from that of other snakes – more evolutionarily derived snakes swallow the prey by alternatively advancing the left and right upper jaw arches (which can move independently) over the prey. But blind snakes don’t have long, independently movable upper jaw and instead “rake” their insect prey into the mouth by stretching and pulling back their short lower (Leptotyphlopidae) or upper (Typhlopidae) jaw. Apparently, smaller species may not even swallow the prey at all, but instead suck the liquid portion of the insect’s body and discard the exoskeleton.

Peter's thread snake (Leptotyphlops scutifrons), the smallest snake in Mozambique.

Peter’s thread snake (Leptotyphlops scutifrons), the smallest snake in Mozambique.

Mozambique Diary: Devonian sashimi

A fishermen from Dingue Dingue and his catch. The first animal is the African lungfish (Protopterus annectens).

A fishermen from Dingue Dingue and his catch. The first animal is the African lungfish (Protopterus annectens).

A few years ago I wrote a book titled “Relics”, which was a way of expressing my fascination with both time travel and with all the irreplaceable forms of life that had existed long before our species sneakily appeared when Nature wasn’t paying attention. One of the organisms I really wanted to include in the book was the lungfish, a direct descendant of the organism that gave rise to all tetrapods, including you and me. Alas, I had never photographed or even seen a lungfish, and thus could not add it to the book.

Imagine my confusion, surprise, delight, disappointment, and hope when yesterday I finally ran across one of those amazing animals. I was driving around with a few friends around an area south of the Gorongosa National Park in Mozambique and at some point we stopped near a small settlement by an old oxbow lake. We saw a few fishermen and decided to see their catch. And there, among catfish and tilapias, I spotted what at first I took for a giant salamander. A second later I realized that I was looking at an African lungfish (Protopterus annectens), a spitting image of Devonian, air-breathing, land-walking animals, the first to evolve lungs, tetrapod locomotion and, as a recent study reveals, structures that eventually lead to the formation of our ears.

Alas, the fish were already dead and gutted. I was heartbroken – it felt to me as if somebody shot a triceratops for its horns or squashed a trilobite as a bug. How can you eat a relic? But my next thought was, since they are already dead, why shouldn’t I eat them? How many biologists could say that they ate a lungfish? Unfortunately, we still had many hours of driving ahead of us and I had no way keeping it cool and safe from the African sun. The only option was to eat it raw. Did I? No, I didn’t, I chickened out, but only because of the fear of contracting some dreadful disease from the water in which the carcasses were washed. But this encounter also made me hopeful that soon I will be able to catch a live one and properly document it. I have just arrived in Gorongosa, and I know that lungfish are here. The hunt commences tomorrow.

Update [4April 2014]: I got it! Read about my encounter with the first live lungfish.Lungfish2