Madagascar Day Gecko (Phelsuma madagascariensis)

I saw this little guy on the cover of one of my favourite animal websites, and he was so bright and pretty that I was immediately interested in writing about him. I will admit that I was also influenced by the fact that I knew I had to draw him. I love using fun colours so that made the Madagascar day gecko a perfect blog candidate.

Madagascar day geckos belong to the family Phelsuma, which contains about seventy species and subspecies. These are commonly known as ‘day geckos,’ as these species are active in the daytime, unlike most other gecko species. The Madagascar day gecko lives in Madagascar (unsurprisingly), along the east coast of the island. There are also introduced populations in Florida. These lizards are arboreal, and are most at home in tropical rainforests.

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Aren’t they cute?

I called them little, but that isn’t very fair. Madagascar day geckos are actually one of the largest species of geckos, reaching lengths of up to 25 cm. As I mentioned, this species is brightly coloured, with the geckos being being bright green or bluish green in colour. They have a rusty-red stripe running from their nose to their eyes, and have various red or brown stripes and spots on their bodies.

Day geckos possess flat toe pads equipped with adhesive scales, which allow them to climb and stick to smooth surfaces. This is no doubt very helpful to a species that spends most of its time hanging around in trees. Day geckos like to relax in their tree perches, soaking up the sun when they’re not looking for food.

Madagascar geckos aren’t exceptionally picky eaters; they feed on a wide variety of invertebrates, as well as fruit and nectar. They get almost all their water from that which collects on leaves, meaning they don’t have to head to the ground to drink. So very convenient.

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My drawing of a day gecko – I had fun with this one though the scales were quite tedious. Still working on getting good scan quality for my pencil crayon drawings, so apologies for that! 

Mating in Madagascar day geckos takes place between November and April. Males attempt to court females by approaching them with their heads moving back and forth. If he is feeling good about his courtship, the male with then grasp the female’s neck with his teeth. After this, the male’s colour darkens, and rests his throat on her head while emitting a soft noise, presumably to comfort her after the trauma of having her head bitten.

Females lay clutches of two eggs, and can lay more than one clutch in a year. The eggs hatch after an incubation period of 47 to 82 days, at which point they are on their own. Like many reptiles, the gender of the young is influenced by temperature; eggs incubated at high temperatures produce males, while lower temperatures produce females. Young geckos are pretty much just tiny versions of the adults, though they are slightly different in colour. They become sexually mature after one or two years of age.

As is so often the case with brightly coloured lizards, Madagascar day geckos are popular as pets. You have to be careful with these guys though — they are very territorial and will act aggressively towards each other if kept in the same tank. Despite their popularity, day geckos are still doing just fine in the wild, which is great news.

Cover image source: Tambako the Jaguar via https://www.jigsawexplorer.com/puzzles/madagascar-day-gecko-jigsaw-puzzle/

Rainbow Agama (Agama agama)

I think there should be one variety of every animal that is rainbow-coloured. Just think of how fun the world would be with rainbow rhinos, rainbow bears, and rainbow alligators. On the other hand, the survival of those species rate might not be very high, since rainbows don’t blend in too well. Still, there are some animals that make a good attempt at being rainbow-coloured, and today’s animal is one of those.

The common agama is found in sub-Saharan Africa, from Gabon in the south to Mauritania in the north and west, and Chad in the east. These lizards can live in a number of different habitats, including urban, suburban and wild areas. As long as these guys have some kind of vegetative cover and insects to feed on, they are quite happy.

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What agamas look like during most of the year. Image credit: Michael Gäbler via Wikipedia

Agamas grow to be a maximum of 25 cm in length, with males being larger than females. They are brown on most of their bodies, with lighter underbellies and greenish heads. Agamas also have a stripe running down their tails, and some fun spots covering their bodies.

They sound pretty boring, don’t they? Well they are, for most of the year. But when the breeding season rolls around and things get steamy, male rainbow agamas start to strut their stuff. Their heads and necks turn a vibrant orange, and their bodies become a radiant blue. It’s no wonder female agamas are attracted to them, because in their breeding colours, male agamas are beautiful.

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A male agama in full breeding regalia. Image source

They are also quite possessive. Agamas live in groups, with a dominant male lording over the rest of the lizards. Only he is allowed to mate, and if any other rapscallion tries to get familiar with one of the females, the dominant male will challenge the unlucky upstart. Fighting consists of males posturing at one another, and then trying to hit each other with their tails.

Females lay five to seven eggs in a shallow hole in the ground. These hatch after eight to ten weeks, and sex is temperature dependent, with males hatching at 29 degrees Celsius, and females hatching at 26-27 degrees. Young agamas stay by themselves for the first few months of their lives, and then live in groups, joining those ruled by mature, dominant males.

So even these lizards, who are named after their rainbow colouring, are only bright and beautiful for part of the year. Still, at least they give it a good try. I give rainbow agamas an A for effort.

Cover image source

Nile Monitor (Varanus niloticus)

There are some pretty terrifying reptiles out there. I’m not really scared of snakes, though some of the more venomous ones would definitely be unpleasant to meet. Crocodiles and Komodo dragons are some I would avoid. And now I get to add another animal to the list: the Nile monitor.

Nile monitors are found along the Nile River, as well as in most areas in sub-Saharan Africa. They live in many different habitats, such as forests, swamps, savanna and scrubland. There are two important habitat features that Nile monitors need: proximity to water and an open area to bask in. Other than that, these guys are pretty adaptable, being excellent climbers and swimmers.

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Nile monitors spend much of their time basking, which sounds like a nice way to make a living. Image source:

Nile monitors are big lizards, and are one of the biggest lizards in Africa. They can grow up to 2.4 m long, and weigh 20 kg, though most are smaller than that. They have well-muscled legs, strong jaws, giant sharp claws, and are just generally built to be badass. Nile monitors are usually dark brown or grey, with yellow and black patterns all over their bodies which can be quite varied.

They prey Nile monitors consume is varied and impressive. Their strong jaws can administer a powerful bite, and are capable of crushing mollusc shells and breaking the necks of small vertebrates. They will eat amphibians, birds, small mammals, lizards, turtles, crocodile eggs and young, and a wide variety of invertebrates. Nile monitors have been observed working together to raid crocodile nests, with one monitor distracting the mother crocodile and the other stealing the eggs.

The combination of a Nile monitor’s strength, size, and speed make them a formidable enemy for any animal. There are, however, some brave creatures that will take monitors on. Pythons are one of these, and it has been reported that a 4.5 m long python fought and ate a 1.4 m Nile monitor, which is pretty impressive. Crocodiles are another occasional predator of Nile monitors, probably because they are getting revenge for their eaten eggs.

The monitor reproductive season begins in June and runs through to October. During this time, the testes of male monitors enlarge, which prepares them for mating. Male Nile monitors are also quite violent, engaging in vicious tussles to prove themselves worthy to mate. Females either lay their eggs in holes they dig or in termite mounds. The eggs can take up to a year to hatch, and often have to wait until it rains so their nest is soft enough for them to burrow out. Occasionally the hatchlings’ mother will come back and dig them out of the nest, but other than that she offers her young no assistance.

Despite their size and ferocity (or perhaps because of it), Nile monitors are reasonably popular as pets. I certainly wouldn’t want one of these beasts in my house, and neither should you.

Cover image source: http://www.skullsunlimited.com/record_variant.php?id=8463

Giant Ameiva (Ameiva ameiva)

Lizards are fun animals. They’re like snakes, but better, because they have legs. I imagine when a snake looks at a lizard the snake gets insanely jealous. And I can’t help but think every time a lizard glances at a snake they smirk at the poor legless creature.

Today’s animal is a lizard that belongs to the whiptail family, Teiidae. Giant ameivas live in Central and South America, and have been introduced to Florida. They are found in a range of habitats, but prefer rain forests that have recently been disturbed.

A male ameiva. He's got some pretty nice camouflage going on there.  Image credit: D. Gordon E. Robertson via Wikipedia

A male ameiva. He’s got some pretty nice camouflage going on there.
Image credit: D. Gordon E. Robertson via Wikipedia

Despite what their name might make you think, giant ameivas don’t get super big. Though I guess giant is a relative term, so maybe an ant named them. Giant ameivas grow to be a maximum length of 16 cm in females and 18 cm in males. Males are mostly bright green, with a brown head and light underbelly. Females are less vibrantly coloured than males.

Reproduction in giant ameivas depends on rainfall. In areas where there is a wet and dry season, the lizards will breed in the rainy season. When there is near constant rain, however, ameivas are able to breed year round. The female lays anywhere from three to eleven eggs,  which hatch in five months. Male ameivas tend to grow faster than females, and the young become mature around eight months of age. Neither parent bothers to look after the eggs once they’re laid.

Giant ameivas have pores on the underside of their hind legs. These pores are used primarily for communication. They secrete chemicals which are signals to other ameivas, and are used in territorial marking and defence, predation, and sexual behaviours. It’s a strange way to communicate, but I guess it works for the ameivas.

An immature male, skulking in some foliage.  Image credit: Dario Sanches via Wikipedia

An immature male, skulking in some foliage.
Image credit: Dario Sanches via Wikipedia

Giant ameivas mainly subsist on insects, though as they get larger their diet starts to include larger animals, such as other lizards. Ameivas are preyed upon by birds and snakes (so I guess the snakes have the last laugh after all). They don’t have any special defences against predation, except for their speed. Their bodies are designed to move quickly, and they rely on this agility to escape their numerous predators. This is why an alternative (and more accurate) name for the giant ameiva is the Amazon racerunner.

I don’t know if anyone has ever held an ameiva race, but people do keep them as pets. They aren’t a great species to have though: they tend to be aggressive and are wonderful carries of salmonella. Still, they are brightly coloured, so people want to have them. I for one would rather not get bitten and contract nasty diseases, but then I’ve never really understood the draw of exotic pets.

Komodo Dragons (Varanus komodoensis)

Due to a crazy week that involves snow, a visiting lecturer, final thesis corrections and me being sick, I invited a friend of mine to do a guest post. Enjoy!

Komodo dragons are probably the closest thing we will ever get to real dragons on Earth. However, don’t allow everything you know about dragons to fool you into thinking these guys are anywhere near as pathetic as their mythological cousins. You read that right, ladies and gentlemen – these dragons are the stuff of nightmares, or at the very least, something straight out of a DnD Monster Manual. These next paragraphs will show you just how terrifying these nightmare-fuel-in-the-form-of-my-mother’s-purse can be.

Komodo dragons can reach up to 3 meters long and tend to weigh around 70 kilograms. They are the largest lizard on earth, yet are only found on a small chain of Indonesian islands, presumably sealed away by the gods before they could take over the earth. There are two pervading theories as to why they are so large: 1) Island gigantism – because there are no other large animals on the island to compete with them, they have been capable of growing as large as their food source (everything, more on this later) has allowed them. The other theory 2) Relict population – they are the remaining descendants of a larger population of (essentially) super lizards that once roamed the earth, known as varanid lizards.

Komodo dragons aren’t only fearsome in size, they are also among the smartest of animals. They belong to a group known as monitor lizards, who have, within the past 10 years, been the subject of multiple psychological tests. Monitor lizards have been shown to exhibit exceptional intelligence, rivaling even that of man’s best friend. Most of these tests have been on some of the smaller monitors, such as iguanas, but some scientists have a death wish, and have managed to conduct a few of these tests on the fearsome Komodo. However, before any of this can even occur, these dragons have to learn not to eat their new scientist buddies. To do this, researchers cleverly removed the dragon’s hunger response in all situations except for “feeding time” (which, I imagine, is a bunch of scientists barricaded in a room, huddled and cowering to the sounds of screaming and carnage). They manage this by pairing a large ball with feeding time (in this case, a large white ball on a stick). When the dragon can see the ball, it knows that it can eat whatever it pleases. As soon as the ball is gone, the Komodo dragon’s thoughts return to its day to day activity, like the torment of human children and kicking puppies (probably). This kind of learning actually takes quite a bit of mental capacity to master, let alone learn at all. It’s a neat trick that allows the researchers to study these dragons without getting their limbs ripped off. But in all seriousness, this is an important step for people who want to interact with Komodo dragons.

The fearsome Komodo dragon.

The fearsome Komodo dragon.

Now we’ve briefly gone over the formidable mind of the Komodo, terrifying in and of itself, we will now move to its impressive biological arsenal (clench what you need to).

Naturally, Komodos are the top predators in their ecosystems. They will eat literally anything, from invertebrates, birds, and mammals. This includes some larger mammals, like deer, which is actually a regular meal for them. Also, due to their flexible skulls and articulated jaws, they can swallow most prey whole. No biggie. To help with sliding entire goats down their throats, Komodos produce a large quantity of saliva to help lubricate their esophagus. Oh, I almost forgot, their saliva is blood red. Komodo dragon’s teeth are actually embedded in their gums, so any kind of strain on their teeth (say, from eating, or licking their lips, or anything really) causes their teeth to cut their gums and bleed. This makes their saliva red (and terrifying), but also a breeding ground for bacteria (more on this later). So we now have a Komodo dragon with a goat halfway down its throat while it oozes red saliva from its mouth. Swallowing said goat can take anywhere from 15-20 minutes. However, Komodos are busy animals, so to speed this process up, they will ram their mouth (and the protruding goat) into trees, rocks or anything else solid enough to withstand the impact (Chuck Norris does wonders for their digestion). Did I also mention that because of its slow digestion, a Komodo dragon can easily survive off 12 meals a year? This allows them to minimize time spent on inane bodily activities, and maximize time spent terrorizing our imagination.

Now, if they cannot simply swallow their prey whole, Komodo dragons will simply bite their prey and wait for a few minutes while their prey dies of pure terror. The mouth of the Komodo (filled with blood, if you remember) is home to some of the worst bacteria known to man. Researchers (with I can only assume one arm) took a sample of the bacteria located within their mouths. Where normal cultures take about 3 days to proliferate, these groups cultured in about 8 hours. It is still a mystery as to why these demons aren’t affected by the plethora of bacteria (approximately 57 different strains), but my theory is that they made a pact with the devil. As if having a CDC outbreak in each of their mouths isn’t bad enough, Komodo dragons also have venom glands. Yup. Komodos have a pair of venom glands that create anticoagulant proteins. This causes you to bleed out faster, and also allows them to bathe in your blood, before deciding to finally eat you.

On top of these deadly biological weapons, the Komodo dragon also have a veritable rock solid defense. While the skin of the Komodo dragon is tough and leathery, it gets its strength from tiny bones embedded throughout its skin. I picture these bones as trophies for each kill, which then adds to their armor, at once protecting itself and intimidating its opponents. These bones, known as osteoderms, are spread throughout the Komodo’s skin, giving the dragon a natural chain mail coating over its entire body. Once it learns how to use medieval weaponry, I fear we will all be doomed.

The harbinger of our doom.

The harbinger of our doom.

So let’s recap. 10 foot lizard-dragon hybrid who’s bite will kill you 10 times over, can swallow most teenagers in a single mouthful, wears its own homemade battle armor, and it’s about as intelligent as the raptors from Jurassic Park? These creatures know not what fear is, except as a gleam in the eyes of anything unfortunate enough to cross its path.

Cover Image source: http://www.bagheera.com/wp-content/uploads/2014/01/komodo_2011.jpg

Chameleon (family Chamaeleonidae)

Chameleons are super cool lizards. I don’t think anyone can deny that. But I didn’t know just how awesome they are until I read up on them for this post. It always astounds me just how little I know of the animal world; no matter what I blog about I always find things I didn’t know about. That’s what makes this blog great, right?

There are around one hundred and sixty species of chameleon that live in a variety of places, including Africa, southern Europe, and western Asia. The majority of species are found in southern Africa and on Madagascar. They can live in lots of different environments, including rain forests, grasslands, mountain forests and sometimes even deserts. Most species of chameleon live in trees, and are highly adapted to this lifestyle.

Many chameleon species have ornamentation on their heads, such as the horns seen on this Jackson chameleon.  Image source: http://www.lizardtypes.com/chameleon-pictures/chameleon-picture9/

Many chameleon species have ornamentation on their heads, such as the horns seen on this Jackson’s chameleon.
Image source: http://www.lizardtypes.com/chameleon-pictures/chameleon-picture9/

One of the main things that help chameleons enjoy a happy life in the trees is the structure of their feet. The toes on each foot are fused together into two groups, making the foot look like a crab claw. These feet not only give the chameleon super funny looking feet, but also are very useful for gripping tree branches. The toes also have sharp claws protruding from them which help the chameleon climb.

Chameleons are most famous for their ability to change colour, something that they accomplish by using special cells called chromatophores. The chameleon has three layers of chromatophores in their skin: a yellow and red layer, a blue and white layer, and a melanin layer, which controls the reflection of light. By manipulation of these layers, chameleons can change into a number of different colours. Colour changes are used for a number of different purposes, not just camouflage. Some species use colour change as a signalling device – they turn darker when angry, but are light and colourful during courtship displays. Desert chameleons use colour change to help with thermoregulation, turning dark in the mornings to get as much heat as possible, and changing to a light colour during the hottest part of the day.

Some species of chameleon are really small - like this one from Madagascar. This is a juvenile, but the species maybe one of the smallest reptiles in the world.  Photo credit: Frank Glaw

Some species of chameleon are really small – like this one from Madagascar. This is a juvenile, but the species may be one of the smallest reptiles in the world.
Photo credit: Frank Glaw

Other notable features of chameleons are their strange-looking eyes and crazy long tongue. Chameleon eyes are very odd. The eyelids are fused together so that only the pupil is revealed, and each eye can move independently. This gives the chameleon full 360 degree vision. They have quite good vision, and are able to see insects from five to ten meters away. Chameleon tongues are designed for the mostly insect-filled diets that almost all species partake in. Chameleons can extend their tongue one and a half to two times the length of their bodies. This happens extraordinarily fast, with tongues able to reach prey in 0.07 seconds. Prey is stuck to the tongue once hit; the tongue has special mechanisms to hold prey in place once caught. Watching chameleons catch prey in slow motion is really cool – I suggest you google it.

With all these crazy features that make chameleons unique among reptiles, it’s no surprise that these lizards are popular pets. Other species are threatened by habitat destruction and pollution, putting many chameleons at risk of extinction. It would be a terrible shame if these quirky, colourful guys disappeared, so let’s hope we can stop that!

Cover image source: http://www.background-free.com/reptiles/lizards/chameleon_hdr.jpg.html