Lizard Land — Part 2 of 2

Green Iguana, Belize, native

 

Last week in Part 1 of this series we looked at lizards’ antipredator adaptations, camouflage, and size. Today we look at their skin, and various ways they move, sense, and communicate.

 

For starters, they are gloriously prehistoric. When you watch a lizard, especially the way it moves, it’s almost as if you are watching a dinosaur. The evolution of reptiles dates back 310-320 million years; more info here. 

 

Marine Iguana, Galapagos Islands

 

Blue-tongued Lizard pair, entwined, Sydney, Australia

 

Spiny-tailed Lizard, Ambergris Caye, Belize

 

Skin. Lizard skin is covered with overlapping scales made of keratin, providing protection from the environment. Scales also help prevent water loss, especially important in hot, dry deserts.

 

This photo shows the textured scales.

Western Fence Lizard, California

 

Tough and leathery, lizard skin is shed as the animal grows; they usually eat it for the minerals.

 

Locomotion.  Lizards live on the ground, in trees, rocks, underground, and even water. Therefore, they move in many different ways.

 

Although there are some legless lizards, most lizards are quadrupedal. Their gait has alternating movement of the right and left limbs, requiring the body to bend–shown in this photo of the Nile monitor.

 

Nile Monitor, Botswana, Africa

 

One of my favorite lizards for their movement is the common basilisk. When alarmed, basilisks rear up on their two hind legs and skitter across the water, earning them the name Jesus Christ Lizard. I’ve seen them run bipedally on the ground as well.

 

This photo demonstrates the basilisk’s muscular hind legs, necessary for bipedal locomotion.

 

Basilisk Lizard, Belize

 

Many species of lizards can effortlessly leap two and three times their body length. Lizards with short legs, like the skink, undulate like a snake.

 

Skink, California

 

Some lizards are extremely fast, while others, especially larger ones, are more languid. In addition, how much sun they have stored in their body is directly relational to speed.

 

The black spiny-tailed iguana (Ctenosaurus similis) is known as the fastest lizard, clocked at 21 mph (34 kph).

 

Black Spiny-tailed Iguana, Ambergris Caye, Belize

 

Geckos get the prize for hanging upside down. Their adhesive toe pads allow them to adhere to most surfaces.

 

The Asian House Gecko has the broadest distribution of any lizard in the world.

 

Asian House Gecko on the ceiling, Kakadu NP, Australia

 

Senses. With over 6,000 species of lizards, there are many variations of how lizards sense their environment–here are a few notable ways.

 

Eyes. Many lizard species, especially iguanas, have a parietal eye, a third eye, on the back of their head. It is photoreceptive and regulates circadian rhythm and hormone production for thermoregulation. Although it does not form images, it is sensitive to light and movement, helpful for detecting predators. The eye is difficult for us to see.

 

A chameleon can steer each eye in opposite directions. Geckos do not have eyelids, so they lick their eyes to keep them clean and moist. Geckos, like monitors, have acute vision.

 

Ears. Instead of external ears, lizards have ear holes or openings. The eardrums, or tympanic membranes, are just below the surface of the skin. These two close-ups clearly show the “ears.”

 

Dragon Lizard, Australia. Ear hole is reddish-brown circle below and left of eye.

 

 

This frill-necked lizard’s ear opening is just right of center photo, in an almost straight line below the eye. Australia.

 

Nose. All lizards, like snakes, have a specialized olfactory system for detecting pheromones or chemical signals. They have a vomeronasal organ (VNO), located in the soft tissue of the nasal septum. When you see a lizard sticking out its forked tongue, as in the photo below, what you are witnessing is the transferring of scent information from the tip of its forked tongue to the VNO.

 

Golden Tegu Lizard with forked tongue out, Trinidad

 

Mouth. Most lizards are predatory and hunt small invertebrates and/or insects. We have lizards to thank for keeping the insect population in check.

 

This western fence lizard had a fruitful day in my backyard. As winged nuptial ants were streaming from a rock fissure, he gorged for at least an hour.

 

Western Fence Lizard, California, eating nuptial ants. Notice all the dead winged ants he hasn’t yet had the chance to consume.

 

Here in California we are lucky to have the western fence lizard, because ticks that feed on this lizard do not spread Lyme disease. This lizard’s blood kills off the Lyme bacteria.

 

The marine iguana, found only in the Galapagos Islands, forages on algae, kelp and other marine plants. They will dive up to 98 feet (30 m), and can stay submerged for an hour.

 

While underwater, marine iguanas ingest salt. The salt is filtered from the blood and then nasally excreted. We saw many of them squirt salt out their nostrils.

 

This photo shows the marine iguana’s lovable face encrusted with algae (green) and dried salt (white) on it.

 

Marine Iguana, Galapagos Islands

 

As squamates, lizards have movable upper jaws, and some lizards, like the green iguana, have very sharp teeth capable of shredding leaves and even human skin. All lizards have teeth, dentition varies.

 

Communication. Lizards make sounds for courtship, territorial defense, and distress signals. Geckos are the most loquacious lizards, with chirps and squeaks that can be surprisingly loud. Sometimes you’ll hear a lizard hiss, a warning.

 

Other forms of communication include:  various body postures like push-ups and head-bobs, as well as the expansion of the dewlap. Tail-flicking is common in territorial disputes.

 

We found this dapper anole with a bright orange dewlap in a Texas swamp.

 

Green anole, Texas

 

This green iguana below, near a river in Costa Rica where it is native, was nearly five feet long (1.5 m) including the tail. An arboreal lizard, they hunt and bask in the trees and can easily break a fall with their hind legs.

 

This photo shows his crescent-shaped, uninflated dewlap under the neck. Dewlaps are muscle-controlled, and help regulate body temperature; also used in courtship and territorial displays.

 

Green Iguana, Costa Rica

 

Leaping Lizards Batman! They are the coolest animal on this planet!

Thanks for joining me in Lizard Land.

 

Written by Jet Eliot.

All photos in the wild, by Athena Alexander.

 

Great Basin Fence Lizard, Great Basin NP, Nevada

 

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Lizard Land — Part 1 of 2

Land Iguana, Galapagos Islands

 

Marine Iguana, Galapagos Islands

Lizards are one of the most diverse and remarkable creatures on this planet; there are 6,000 species living on all the continents except Antarctica. Here are some of my favorites in this two-part series.

 

Although most lizards may seem vulnerable as fairly small, soft-sided creatures, they are hearty and flourishing survivors.

 

It is their antipredator adaptations that have rewarded lizards with success on the planet. Features such as camouflage, self-amputation, venom, and reflex bleeding aid these reptiles in numerous ways.

 

Camouflage. In the Hawaiian tropics, this gecko surprisingly blends into the lush tropical flowers and greenery. We were lucky to find this one on our rental car where it stood out.

 

Gold Dust Day Gecko, Hawaii

 

Here you see the Lobed Chameleon in Serengeti grass…barely noticeable in its camouflaged state. Imagine how many ferocious wild African species could eat this palm-sized chameleon…yet in Tanzania alone there are 100 species of chameleons.

Lobed Chameleon, Serengeti, Africa (in exact center of photo)

 

The chameleon, like many lizard species, changes color to hide from predators. They also have the ability to extend their long, sticky tongue to snap up insects without having to leave their hiding spot.

 

This frisky pair of spiny-tailed iguanas would have escaped our notice if they hadn’t been rustling in their chasing.

 

Spiny-tailed Iguana pair, Belize

 

We found a frill-necked lizard on every tree in this northern Australia eucalyptus forest. Invisible to us at first, the guide pointed them out.

Frill-necked Lizard, Atherton Tablelands, Australia

In addition to camouflaging, the frill-necked lizards have a unique scare tactic. Named for the ruff of skin around their neck, frill-necked lizards can expand their neck skin like the instant opening of an umbrella. They have bones in the frill that form rods extending their ruff, quickly transforming them to be bigger and more fierce.

 

This is a good BBC YouTube video of what the frill-necked lizard looks like when defending. 

 

Self-amputation. Another example of anti-predator adaptation is autotomy or self-amputation. Skinks and small lizards are known for their ability to escape from a predator by this method.

 

If a predator grabs onto their tail, they sacrifice it by ejecting it, and escape, leaving the predator with only a still-squiggling tail. Miraculously, they grow the tail back. It has been found that lizard DNA is responsible for regeneration, involving 326 genes.

 

You can see this lizard with its battle scars: a segmented tail, indicative of regrowth.

Green Anole, Costa Rica; segmented tail indicating regeneration

 

Venom. While most lizards are not harmful, there are a few who produce venom, like the Gila monster, Komodo dragon, and some monitors. Lizard venom has led to ongoing scientific research for medicinal drugs to help with blood clotting, weight loss, and diabetes.

 

Reflex Bleeding. Horned lizards have an antipredator adaptation called reflex bleeding. At least eight species of this lizard can squirt and aim a stream of blood from the corner of their eyes, shooting it a distance of up to five feet (1.5 m). The blood confuses the predator, and is also foul-tasting to dogs and cats.

 

Another extraordinary lizard characteristic is thermoregulation. As cold-blooded animals, they rely on the sun for supplying energy to move and function. For this reason, lizards can often be seen basking in the sun.

 

Marine Iguana colony, Galapagos Islands

 

Basilisk Lizard, Belize, Central America

 

Lastly, lizards vary incredibly in size and shape. This land iguana is one of the largest lizards in the world, weighing up to 25 pounds (11 kg) and measuring 3-5 feet long (0.9-1.5 m).

Land Iguana, Galapagos Islands

 

In contrast, this full adult gecko, aptly named the dwarf gecko, is half as big as a paperclip.

Dwarf Gecko, Belize

 

And finally, as an aficionado of wild lizards, I ask that if you ever seek to purchase a lizard for a pet, please be responsible in purchasing only lizards that are bred in captivity and legally bought and sold. Help keep our wild lizards wild.

 

Solar-generated animals that can change colors, regrow their tail, magically blend into their surroundings, and shoot blood. How incredible is that?

 

Written by Jet Eliot.

All photos in the wild, by Athena Alexander.

See you next Friday for Part 2 of Lizard Land. Thanks for joining me!

Western Fence Lizard, California

 

Two Night Drives

Black and White Owl, Belize

It was the same territory we had traversed every day in this Belizean rainforest, but a very different world opened up once the jungle night unfolded.

 

Night drives involve a vehicle with a strong spotlight hooked up to the battery, and one or two guides who drive and spot. Athena and I stood in the back of a pick-up truck–hanging on, dodging palm fronds, and swatting at mosquitoes.

 

Baird’s Tapir, adult female, Belize

Tapirs were a great find, and one of our favorite adventures of the whole trip. More about that: Tapir Time.

 

But we came upon so many other creatures too.

 

Mottled Owl, Belize

 

Owls and bats are a big draw on night drives, and the Belizean forest did not disappoint. I’m always happy to see bats because it means there is a balance in the ecosystem. We saw about 20 individual bats on our two night drives. The lights on the vehicle brought them in, for the insects, then they’d spin away into the black oblivion.

 

We spotted this spectacled owl with a snake. When we drove off, we watched the owl carry the Fer-de-lance snake, highly venemous, back to a palm tree where we suspected there was a nest.

 

Spectacled Owl with Fer-de-lance snake

 

Owls and bats are not the only nocturnal flyers. There were also common pauraques and northern potoos, bird species in the nightjar family (Caprimulgiformes).

 

Pauraques were especially prevalent in this rainforest. When they aren’t flying, they are on the ground, camouflaged in leaf litter; this parent was hiding a little one.

 

Common Parauque adult sitting on top of chick

 

They feed on insects, and were attracted to the constant bug flurry around the lodge’s landscape lights. I heard them every night, so loud that sometimes they woke me up.

 

Sound of pauraque in night forest. 

 

At one point, the driver spotted a wild cat called a margay. We had a two-second look at it before he or she disappeared into the forest. Camouflage spots, quick and stealthy…gone in a flash.

 

Margay. Photo: Brian Gratwicke, courtesy Wikipedia.

They are small, the size of an ocelot, native to Belize, and nocturnal. Their populations are declining, so we were happy to see this rare wild cat.

 

There were large moths and small; beady eyes looking out of the tangled trees; lots of croaking frogs. We came upon a raccoon who was hunting high in a tree; and deer in their nighttime mode, frozen in place by the spotlight. This mammal emerged out of the shadows and it took a few seconds to see it was a tapir.

 

Tapir (center) coming out of the jungle shadows

 

Every day we saw cattle in a pasture on the edge of the forest. At dawn we were there chasing parrots and toucans, while the cattle unabashedly stared at us. When we came back at night, their shining eyes were still staring at us.

 

Cattle in pasture

 

One night we were walking on the lodge grounds when we heard a plop, and found this cane toad, a native.

 

Cane toad, Rhinella marina

 

It’s cooler at night, and the moving vehicle creates a wind that feels luxurious after a long, sweaty day. But the best part of the night drives is seeing this mysterious nocturnal world come alive.

 

Written by Jet Eliot.

Photos by Athena Alexander except margay.

Baird’s Tapir, juvenile and mother, Belize

 

 

Parade of Leafcutter Ants

2013

Leafcutter Ants, Belize

Leafcutter ants are productive farmers with an elaborate society based on ant-fungus mutualism; i.e., a symbiotic relationship between the ant and the fungus. One day last month I had the joy of watching some especially clever ants taking a shortcut.

 

The ants get safe, underground living accommodations from the fungus, including a means to feed their ant larvae. And in turn, the ants keep the fungus fed and cleaned. Although the ants don’t actually eat from their fungal garden, they chew up the delivered leaves to decompose for the nest.

 

Many colonies contain approximately one million ants, but there can be as many as 8-10 million ants.

 

The ants bite off a piece of leaf and carry it back to the fungal garden, their underground nest. This is what we humans see as each ant carries a leaf chunk down the trail. An underground nest can grow to more than 98 feet (30 m) across, with additional chambers leading off of that.

 

Leafcutter Ant carrying leaf spear

There are many tasks in a community this large, and each individual has a specific role including the queen, several castes of workers, foragers, and soldiers.

 

Next to humans, they have the largest and most complex animal society on earth.

 

Leafcutter Ants Wikipedia

 

I’ve seen leafcutter ants in many tropical venues, and always on a forest trail or in grass. They often have a conspicuous trail, because there are so many ants moving back and forth that eventually they wear down the vegetation, as seen here.

 

Leafcutter Ant trails in grass (bottom right and leading from plant on top left)

 

Lodge Pool, Belize

 

One day Athena and I were swimming at the lodge pool, when we noticed little morsels of leaf parading across the floor tiles. There weren’t that many, maybe one ant every foot (.30 meter) or so. I don’t think other people would have even noticed them, but I am always on the lookout for leafcutters, because I think they are one of the most amazing creatures on earth.

 

The stamina! The industriousness! The tenacity of a leafcutter ant is completely inspiring. Their strength is astounding. They can carry 12-20 times their body weight.

 

After some investigation, we discovered they were taking a rainforest shortcut through the pool area. They entered at one end of the pool enclosure, walked across the pink floor tiles, and exited at the other end. This was about a 50-60 foot long (15-18 m) trail. They traveled along the floor edge, near the plantings, under the lounge chairs.

 

There were places where water was on the floor, which upset the parade. A simple small puddle threw off their scent. Here they circled around for a half minute or so, but would then stabilize, get back on track, and eventually find their way to the exit rock.

Leafcutter Ant disoriented by water spot

Each one took the exact same trail, and they all vanished at the same place. The exit rock is in the center of this photo below–there was a gap between the second and third rocks, about the size of a fist.

Rock exit, between second and third rocks

 

Ant with leaf exiting, in shadow of rock on right

As the plot thickened, we went outside the pool enclosure, thinking there would be a continued trail. But instead they were gone. They had vanished underground, reached their destination. There we stood in our dripping pool clothes, fascinated.

 

It was a very hot, humid day; all the birds were resting, all the humans were resting. But the leafcutter ants, they just kept marching.

 

Written by Jet Eliot.

Photos by Athena Alexander.

Leafcutter Ants, Costa Rica

 

Long-tailed Birds

Resplendent Quetzal (male), Costa Rica

 

Fork-tailed Flycatcher (male), Belize

Every once in a while I come across a bird with a spectacularly long tail. It happened last month with this Fork-tailed Flycatcher in Belize. When the bird flies, his long tail ripples gracefully in the wind.

 

One day long ago, while I was still in birding classes, I was standing in my mother’s backyard, a suburb near Dallas not far from fields. I looked up and saw a beautiful bird on the telephone lines with the longest tail I had ever seen in my life. Later I was to learn it was the scissor-tailed flycatcher, not uncommon in Texas.

 

And since then, I have had the pleasure of collecting many beautiful images of birds with lengthy tails.

 

We were flying down a Mexican highway in a cab one day, when we spotted this jay on the lines. Screeched to a halt.

 

Black-throated Magpie Jay (male), Mexico

 

In some long-tailed bird species, only the male has the long tail; in other species, like motmots, both genders have the long tail.

 

There are numerous evolution theories as to why a species has a long tail. Most theories posit that the male’s long tail is a signal to the female of good breeding foundation.

 

Some species have cord-like streamers, whereas others, like my favorite the resplendent quetzal, have more of a double ribbon for a tail.

 

Motmots, a colorful Neotropic bird, have long tails shaped like racquets.

 

Turquoise-browed Motmot, Costa Rica

 

This hummingbird has a racquet-tail too.

Booted Racket-tail Hummingbird (male), Peru

 

One of the most striking birds on the planet, the resplendent quetzal male has a long tail that sparkles in the sunlight. For an hour we watched this male in a Costa Rican mountain rainforest eating avocadoes. Then when he was satiated, he flew on.

 

We instinctively ran after him, enchanted by the magic, the beauty.

 

Undulating behind this showy bird, the iridescent tail shimmered and flowed in the most natural ribbon-like spectacle. Eventually the bird disappeared into the forest.

 

Resplendent Quetzal (male), Costa Rica

 

In the red-billed tropicbird, the male’s tail streamer is slightly longer than the female’s, about 4.7 inches (12 cm).

 

We once went to a breeding colony of tropicbirds on the island of Little Tobago in the West Indies. The tropicbirds were competing with frigatebirds over food, and the guide told us that sometimes a frigatebird would pluck at a tropicbird’s long streamers, try to pull it out.

 

Red-billed Tropicbird, Little Tobago Island, West Indies

 

Birds that wear party streamers for tails:  they make you want to sing and dance and go a little wild.

 

Written by Jet Eliot.

All photos by Athena Alexander.

Indian Peacock in Texas

 

Tapir Time

Baird’s Tapir, female adult, Belize

Tapirs are large, four-legged mammals found primarily in the jungles of Central and South America. They are rare. How very exciting it was then, to have ten minutes in the wild with this magnificent animal.

 

Adding to the difficulty of finding them, they are nocturnal, and classified as Endangered or Vulnerable. Currently there are five tapir species in the world, with one small population in Southeast Asia and all the rest in the New World. The list of extinct tapir species is far longer than the extant list.

 

Tapir Wikipedia.  Pronounced TAY-peer. We observed the Baird’s Tapir species.

 

Athena and I were on a night drive, standing in the back of a pick-up truck in the jungles of Belize. We had two guides: one was driving, the other was spotting, i.e. shining a strong spotlight on the trees as we drove along.

 

Five minutes after we began, the driver stopped and turned off the truck. None of us spoke. With the aid of the spotlight, we could see branches moving a few feet ahead, and just then a long snout reached out of the thicket.

 

In spite of our excitement we stayed silent, inviting it to come out so we could see it better.

 

Then another snout, this one considerably smaller, peered out from behind the branches; and the mother and juvenile cautiously but steadily walked out of the forest. Their eight hooves clopped as they tentatively walked in front of our truck and crossed the narrow road.

 

Baird’s Tapir, juvenile and mother, Belize

 

As they crossed, the adult tapir wiggled her wet nose, sniffing our scent as she determined if she and her youngster were safe.

 

Apparently she knew we were there only to admire, for she led her youth forward and they casually continued to eat the leaves. Baby tapirs are striped and spotted; this juvenile, with no more baby skin, was estimated to be 1.5 years old.

 

Baird’s Tapirs, Belize, juvenile facing camera

 

The largest native herbivore in the New World tropics, tapirs are usually wary of humans, for they have been hunted close to extinction, and their forest habitat continues to disappear. But we were in a preserve where they are surrounded by forest and protected.

 

Here we were all safe in the dark rainforest, with moths and bats and low-hanging palm fronds casting eerie shadows. We were fellow mammals curiously looking at one another.

 

Their long proboscis noses wiggled and sniffed.  On both tapirs the elephantine snout sniffed the leaves and tore them from the branch, shoveling the greenery into the mouth.

 

Baird’s Tapir, adult female, Belize

 

As we continued to watch, I was frequently reminded of other mammals. The elephant came quickly to mind. Tapirs use their prehensile noses for grasping, just like the elephant with its trunk. Their gentle disposition also reminded me of elephants. The clopping sound of their ungulate hooves reminded me of horses.

 

When they walked very close to the back of our vehicle, I remember wondering if they could charge like their perissodactyl relative the rhinoceros.

 

An adult tapir weighs about 500 pounds (227 kg).

 

Baird’s Tapir, front hoof

Tapirs have a very thick skin which aids them when the wild cats pounce on them. Their tough skin can retract, rejecting the cat claws. And if a cat still insists on hanging on, the tapir will violently run through the jungle slamming the cat against a tree.

 

But that night there was no slamming or charging. Mosquitoes were biting, moths and bats were swooping, but the tapirs just meandered along…no hurries, no worries.

 

They walked a full circle around us, first crossing the road in front of the truck, eating leaves on our right, then crossing the road in back, and eating the leaves on our left. Soon after that, they vanished into the forest.

 

Written by Jet Eliot.

Photos by Athena Alexander.

Baird’s Tapirs, eating

 

Thirsty Butterflies

Dark Kite-swallowtail Butterfly, Belize

We had been birding the Belizean tropical jungle for days, when a new phenomenon greeted us one dawn morning: clouds of butterflies congregating around the ground.

 

Up until then, we had been seeing that same species, the Dark Kite-swallowtail butterfly, flying around all week. One or two, here and there, on flowers–like usual.

 

But this day they were in clumps of 40 and 50, always on the earth.

 

Dark Kite-swallowtail Butterflies, Belize

 

Rainforest

There were hundreds, and as we headed down the road to our destination–to watch toucans feeding–we watched them flutter all around, quite magical.

 

They were all on the road and the dirt, and as our truck trundled by I was nervous for their safety. They could easily be run over.

 

I asked the guide, “Why are all the butterflies around this morning? And in such big groups?” It was 6 a.m., no one was especially gregarious yet.

 

He explained that due to the rain we’d had the night before, the ground was moist, and the butterflies were drinking the water.

 

Keel-billed Toucan, Belize’s national bird

 

Hours after we’d watched the toucans, we came upon the local village’s small airport hangar, and found a drainpipe surrounded by the swallowtail butterflies. It’s hard to make out, but that dark smudge in the bottom right of this photo, right of the drainpipe, is all butterflies…at least a hundred. They were having a drinking party.

Black Kite-swallowtail Butterflies at base of drainpipe between building and road, Belize

 

Every butterfly has a proboscis and a pair of antennae. The proboscis is a mouth part, used for sucking. It is a long tube (technically, two tubes) with muscles; part of the digestive system. We don’t always see a butterfly’s proboscis because it can be coiled-up, out of sight.

 

Their antennae, generally club-shaped, have a different function: as receptors, and for balancing.

Butterfly anatomy

from enchantedlearning.com

 

 

 

 

 

 

That day, each individual was using its proboscis to suck water from the ground.

 

The butterfly uses the proboscis not only for sucking water, but also for sucking nectar and sometimes, for extracting minerals. If you’ve ever witnessed a butterfly landing on a person’s skin, the insect is seeking the mineral salt in human sweat.

 

It was windy and the gusts were blowing their long-tailed wings, but each individual steadily continued to drink the rainwater, undeterred.

 

Everyday in the rainforest it was very hot and humid and we were always hot and thirsty…but who would’ve guessed that the butterflies were thirsty?

 

Written by Jet Eliot.

Photos by Athena Alexander.

 

Black Kite-swallowtail Butterflies, Belize