Skink Vs Lizard: Understanding The Key Differences

Lizards and skinks have often been confused as the same type of reptile. However, while they share similarities, skinks are actually a unique family of lizards with distinct traits that set them apart.

If you’re short on time, here’s a quick answer: Skinks are a family of reptiles in the larger lizard order Squamata. Lizards include skinks but refer to a broader category of reptiles. Skinks differ from other lizards by having a shiny, blue-colored body and fused eyelids.

In this comprehensive 3000-word article, we will explore what defines lizards and skinks, examine their similarities and differences in appearance, size, habitat, behavior, and reproduction. We will provide detailed overview of 6 major skink species and bust some common myths about skinks vs lizards.

Defining Lizards vs Skinks Scientifically

The Scientific Classification of Lizards

Lizards belong to the reptile order Squamata, which also includes snakes. More specifically, lizards fall under the suborder Lacertilia. There are over 6,000 lizard species that have been identified so far.

Lizards are generally characterized by a long body and tail, four legs, movable eyelids, and external ear openings.

What are Skinks Scientifically Speaking?

Skinks are a large family of lizards under the scientific family name Scincidae. There are over 1,500 identified skink species. Like all lizards, skinks belong to the order Squamata. They are distinguished by their smooth and shiny scales, giving them a glossy appearance.

Most skinks also have relatively small limbs compared to other lizards.

Lizards – A Broader Reptile Group

As a lizard subfamily, skinks are considered a type of lizard. However, lizards encompass a much broader range of reptiles outside of just the skink family. For example, some other common lizard groups include geckos, iguanas, monitors, chameleons, and more.

So while skinks fall under the larger lizard classification, most lizards are not skinks.

To summarize:

• Lizards = Reptiles under order Squamata, suborder Lacertilia. Diverse group with over 6,000 species.
• Skinks = A specific lizard family called Scincidae, with around 1,500 species.
• Skinks are a type of lizard, but only make up a small subset of the total lizard population.

Appearance: Key Physical Differences

Skink Coloration and Skin

Skinks come in a rainbow of colors like red, blue, yellow, and green. Some species even have striking patterns like bands, spots, or stripes. Their skin has shiny scales and most don’t have elongated spikes or horns like other lizards.

These unique colors and textures help skinks camouflage in their environments. For example, the five-lined skink’s stripes resemble blades of grass.

Skink Size vs Other Lizards

On average, mature skinks are smaller than most traditional lizards. Their size ranges widely from the minute ground skink at just 3 inches long to the giant blue-tongued skink over 2 feet long. Though they vary greatly in dimensions, most species of skinks measure under 12 inches snout to tail tip.

By comparison, popular pet lizards like leopard geckos reach up to 11 inches and bearded dragons up to 24 inches full grown. So while some skinks rival the length of these lizards, many remain petite their whole lives.

Fused Eyelids of Skinks

A trademark physical feature that sets skinks apart is their fused eyelids. Called a spectacle, their translucent eyecaps protect their eyeballs from dirt and debris. The only time the skin separates is during shedding. Plus, skinks often have dark bands across their eyes resembling thick eyeliner!

Conversely, most lizards including geckos and iguanas boast flexible upper and lower lids with a nictitating membrane for extra coverage. Being able to open and shut their eyes likely provides better vision clarity.

Leg and Body Shape Differences

Skinks sport a long, cylindrical-shaped body and tail with four legs. Their build suits an ambush lifestyle burrowing underground or hiding in vegetation. When needed, their strong legs allow them to sprint at high speeds.

In comparison, many common pet lizards have stockier bodies, shorter tails, and only two usable legs like leopard geckos. Or some lizards lack legs entirely and instead have serpent-like bodies like the slow worm or glass lizard.

Habitat: Where Skinks and Lizards Live

Deserts and Dry Areas

Many lizard species inhabit hot, arid desert environments around the world. Over 60 lizard species are found in the Sahara Desert alone. Desert-dwelling lizards like the Mojave fringe-toed lizard have special adaptations allowing them to thrive in extremely dry conditions, such as the ability to minimize water loss.

Some skinks also inhabit deserts and dry scrublands, but they tend to require slightly more moisture than true desert lizards.

Forests and Jungles

Lush tropical forests and jungles harbor an abundance of both skinks and lizards suited to warm, humid environments. Tree-dwelling lizard species like chameleons, anoles, and geckos camouflage themselves among jungle vegetation and hunt insect prey.

Ground-dwelling tropical skinks forage among the leaf litter and hide from predators amidst roots and fallen logs. Overall lizards show greater diversity and adaptability to tropical habitats compared to skinks.

Urban Environments

While most lizards and skinks shy away from human activity, some species have adapted surprisingly well to man-made urban settings. Lizards like the Mediterranean house gecko and Italian wall lizard are now common inhabitants of cities worldwide thanks to their tolerance of disturbed environments.

Some skinks have also established urban populations, such as the five-lined skink which shelters in old walls, sidewalk crevices, wood piles, and abandoned buildings across North American cities.

For more details on lizard and skink habitats, check out the San Diego Zoo’s lizard and skink facts pages.

Behavioral Variances Between Groups

Daily Activity Cycles

Skinks and lizards have differing daily activity patterns. Skinks tend to be diurnal, meaning they are most active during the day. Lizards display more variation – some species are diurnal while others are crepuscular (active at dawn and dusk) or nocturnal.

The activity patterns likely developed as adaptations to regulate body temperature and avoid predators in their native habitats.

Social Structures

There is also variation in the social structures of skinks vs. lizards. Most skinks are solitary creatures that only interact with others of their species during mating season. In contrast, various lizard species demonstrate complex social groupings and long-term pair bonding.

For example, certain iguanas form family units with dominant breeding pairs and juvenile subgroups living communally in shared territories.

Hunting and Feeding Habits

As ectothermic reptiles, both skinks and lizards must bask to regulate body temperature and become active enough to hunt prey. However, their diets and hunting techniques differ. Skinks mostly feed on insects and larvae detected while moving continuously across the ground.

Lizards often ambush prey by remaining stationary then striking with speed and agility. For instance, chameleons have specialized eyes and projecting tongues allowing them to stealthily scan for and capture passing insects and small vertebrates from branches.

Defense Mechanisms

When facing threats, skinks and lizards employ an arsenal of self-preservation tactics. Skinks primarily flee quickly to vegetative cover or soil burrows. Various lizards may compress their bodies to fit crevices, change color to camouflage with surroundings, regrow detached tails to distract predators, or even spray blood from their eyes to startle attackers.

So each group has evolved specialized physical and behavioral adaptations for defense and damage control.

Reproduction and Life Cycles

Gestation Periods

When it comes to reproduction, skinks and lizards have some similarities but also key differences. Let’s start with gestation periods. The gestation period for skinks ranges from 6-8 weeks depending on species, while for lizards it can vary widely from just 4-6 weeks for small species to up to a year for larger lizards!

Birthing Live Young vs Eggs

Another major difference is that most skinks give birth to live young while the majority of lizards lay eggs. For example, common garden skinks bear their babies live rather than laying eggs. However, there are a few skink species that do lay eggs like some blue-tongued skinks.

Parental Care Behaviors

In terms of caring for babies, skinks exhibit more parental care compared to most lizards. Female skinks will guard eggs and then newborn offspring for some time before the babies disperse. Male skinks may also defend territories and protect juveniles.

Conversely, the vast majority of lizards show no parental care at all and the eggs/newborns are left to fend for themselves.

Lifespans

When it comes to longevity, skinks generally live shorter lives on average compared to many lizards. Small skink species may only survive 1-2 years in the wild. Large skink species can live around 5-6 years on average.

In contrast, various small lizard species can live 5-10 years, while large lizard species can survive 10-20+ years!

To summarize, skinks and lizards share some reproductive similarities but have clear differences when it comes to gestation lengths, birthing methods, parental behaviors, and lifespans. Skinks tend to have shorter gestation then give birth to live young which they care for to some degree, while lizards lay eggs and provide little to no care with some species living significantly longer life spans.

Understanding these key variances can help people better differentiate between skinks and lizards!

For more detailed information on skink reproduction and life cycles, check out these great resources:

• https://reptilesmagazine.com/skink-reproduction-and-life-cycles/
• https://www.jstor.org/stable/3892917

6 Major Types of Skinks

Blue-Tongued Skinks

Blue-tongued skinks are one of the most popular pet skinks. These lizards are native to Australia and New Guinea. They get their name from their bright blue tongues, which they use as a warning to potential predators. Blue-tongues grow up to 24 inches long and live 10-20 years in captivity.

They are omnivores who enjoy a varied diet of fruits, vegetables, insects, and small rodents. Blue-tongued skinks are docile and make great beginner lizards for reptile enthusiasts.

Fence Lizards

Fence lizards, also called blue bellies, are common lizards found throughout the western United States. There are over a dozen recognized subspecies of fence lizards that vary in color patterns. Most fence lizards grow 4-8 inches in length.

These skinks are very agile climbers and earned their name because they are often seen sunning themselves on fences or logs. Fence lizards feed on insects and other small invertebrates. Males bob their heads during breeding season to attract females.

Five-Lined Skinks

As the name suggests, five-lined skinks have 5 longitudinal stripes running down their backs and tails. They are medium-sized lizards measuring 5-8 inches long. Five-lined skinks are common in the eastern United States and other parts of North America.

They are ground-dwelling lizards that hide under rocks, logs, and leaf litter in the forest. Fast and energetic, these skinks prey on various insects, spiders, snails, and worms. Five-lined skinks are ovoviviparous – the eggs hatch inside the female’s body just prior to birth.

Ground Skinks

There are nearly a dozen species of ground skinks found across North America. Most species are small, growing 3-6 inches in length. As their name suggests, ground skinks are terrestrial and typically found under logs, leaf litter, or burrowed into loose soil.

Ground skinks have smooth shiny scales and short legs. They come in brown, olive, or gray colors to help camouflage themselves among the forest floor debris. Ground skinks prey on insects, larvae, worms, and snails.

Sand Skinks

The sand skink is a small legless lizard that inhabits the southeastern United States. Growing up to 7 inches long, the sand skink has a snake-like body adapted for burrowing through loose sandy soils. Its small limbs are barely visible outside the body.

Sand skinks feed on insects and larvae found among beach dunes and pine forests. They play an important role distributing seeds and nutrients through the substrate. Unfortunately, habitat destruction has made the sand skink a threatened species in many areas.

Skinks

Skinks comprise one of the largest lizard families, with over 1,500 known species. Most skinks look like typical lizards, with elongated bodies, four legs, long tails, and shiny oval scales. Skinks come in a huge range of colors, sizes, and habitats.

As a family, they inhabit tropical, subtropical, temperate, and desert regions around the world. Most skinks are terrestrial or fossorial (burrowing), with some being good swimmers or climbers. They fill ecological roles as predators, prey, seed dispersers, and pest controllers that help balance healthy ecosystems.

Common Myths and Misconceptions

Myth 1: Skinks are Baby Lizards

This is one of the most prevalent myths about skinks. Many people think skinks are simply juvenile or baby lizards that haven’t fully grown yet. However, this is incorrect – skinks are a distinct type of lizard within the large Scincidae family, and not the offspring of other lizards.

While young skinks may resemble baby lizards due to their small size, they are actually full-grown adults. Skinks come in a huge range of sizes – from minute species just a few centimeters long to the massive blue-tongued skink reaching 60 cm.

So size alone cannot distinguish a skink from a juvenile lizard.

Skinks also have several physical differences from other lizards like smaller legs or reduced limbs, elongated bodies, fusiform shape, and smooth glossy scales. These specialized adaptations help them excel at burrowing and sliding through vegetation.

Therefore, skinks should not be mistaken as baby lizards based solely on appearances.

Myth 2: Skinks are Venomous

While a small number of lizards like the Gila monster produce venom, skinks are not venomous species. They do not have any venom glands or venom delivery apparatus like hollow or grooved teeth.

Some reasons why skinks may be erroneously assumed to be venomous include:

• Bright aposematic warning coloration seen in some species can give the impression they are dangerous.
• tendency to leave behind wiggling detached tails when threatened, making them appear threatening.
• ability to inflict nasty bites with their sharp teeth that bleed profusely.

However, even the most painful skink bites are not medically significant. The bleeding is simply due to thin skin over bony protrusions getting torn up by their teeth.

Myth 3: Skinks Make Good Pets for Children

Small size and cute appearances tend to give the impression skinks would suit young children well as starter pets. However, there are a few reasons why skinks may not be ideal pets for kids:

• Many species are exceptionally fast moving, making them difficult for small hands to catch and hold.
• Some become stressed by excessive loud noises, erratic movements which children exhibit while playing.
• Their small size also makes them prone to accidental injury if handled roughly.

Therefore, skinks may not be the most suitable pet lizards for young children in most cases. Parents should thoroughly research particular species care needs and temperaments before allowing kids to keep them. Supervising all interactions is a must.

Conclusion

In summary, while skinks fall under the broad classification of lizards, they have distinct physical attributes and behaviors that differentiate them as unique. Their blue tones, fused eyelids, preferences for certain habitats and diets all set them apart from other lizard species.

Understanding what defines a skink allows us to appreciate them as fascinating reptiles in their own right. We can also better provide appropriate care guidelines for the different skink species when kept as pets. If their needs are met, skinks can make for delightful additions and enrich our lives.