Tarantula eyes work a little differently from ours since they have so many of them. Despite having many eyes, they don’t see particularly well, and they rely on other senses instead. Understanding how tarantula eyes work will help you understand your tarantulas’ needs and care for them better.
Tarantulas have eight eyes which are very “simple” compared to other invertebrates. They have two big eyes in the middle of their cephalothorax and four smaller eyes beneath those. There are also two eyes on the sides for additional vision and information on their surroundings.
This article will cover everything to do with tarantula eyes, including how their eyes work and what kind of eyes they have. Our goal is to help you provide your tarantula with better care to improve their lives as a pet.
Why do Tarantulas Have Eight Eyes?
Tarantulas have “simple eyes”, which means they don’t have amazing vision. They can detect the size, shape and sometimes the colour of nearby objects. However, tarantulas need to turn their entire body to look around so having extra eyes gives them a bigger vision range.
Being unable to turn your head to look around is a significant disadvantage. Tarantulas evolved additional eyes to give them a broader vision range to compensate for this. Tarantulas have eight eyes, with two large ones and a row of four smaller eyes underneath. They also have another two eyes on the sides close to their other eyes.
Tarantula eyes also perform different jobs. The two big eyes are used to detect the size, shape and colour of nearby objects. Underneath are the four smaller eyes, which are primarily used for distance estimation and additional peripheral vision. The extra two eyes also give the tarantula a broader scope of vision without needing to turn their entire body to look in a specific direction.
What are Tarantula Eyes Like?
Tarantulas have “Simple Eyes”, so they lack an elaborate retina like we have. The two large eyes are used to detect size and the four smaller eyes beneath are for distance estimation and additional vision. The two eyes slightly away from the others allow tarantulas to see around them without turning their bodies to face it.
Arachnids have simple eyes, which means each eye only has one lens to receive and process visual information. Tarantulas might have a lot of eyes, but they have minimal vision. They have eyes that can only detect shapes, movement and colour are suspected as well. Research into tarantula vision is minimal, though we know they cannot see very well. This is why tarantulas are so sensitive to sounds and vibrations; they rely on these instead.
Tarantula eyes are different to most other insects, which have “compound eyes”. Many other insects have large “compound eyes”, which are made up of multiple small lenses. Compound eyes have a much greater field of view, and they are confirmed to differentiate between colour and brightness levels. They are also good at detecting motion, which is why many insects respond better to moving objects than stationary ones.
How do Tarantulas see with Eight Eyes?
The vision interpretation process is similar to ours. Tarantula eyes send the visual information to their ‘brain’ so it can be interpreted. They have tiny brains made up of two simple nerve cell clusters, which allows them to perform complex tasks and see.
Spider vision is different across species, but we know tarantulas have limited vision. They can still process and interpret what they see since the information is sent to the brain. Our eyes work the same way though we have “Camera Type Eyes”, which focus light onto the retina before sending it to the brain for processing.
Where are Tarantula Eyes Located?
Tarantula eyes are located at the front of the cephalothorax and slightly above the chelicerae. Their eyes are usually in a small cluster in the middle and just above the fans. They always have two large eyes then four smaller ones underneath. Tarantulas also have two additional eyes on the side, slightly away from the others.
Eye location can change slightly between different spiders, but tarantulas generally have eyes in the same position. True spiders can have slightly different eyes that perform different jobs to a tarantula. An excellent example of this is jumping spiders with eyes specially designed for a task and giving them almost a 360-degree view. Tarantulas don’t need vision this good as they have very sensitive hairs that allow them to understand the world around them.
Do All Tarantulas Have Eight Eyes?
All tarantulas have eight eyes, but this is not always true for spiders in general. Tarantulas have two large main eyes with four smaller eyes underneath. They also have two additional eyes on the sides to offer peripheral vision.
Tarantula eyes are located on the cephalothorax just above the chelicerae and are usually in a small cluster. Their two large and four smaller eyes are close together, and the other two can be seen away from the others. However, true spiders don’t always have eight eyes.
Do All Spiders have Eight Eyes?
Spiders always have a pair of eyes, and always in an even number, there are no spiders with a single eye. Most species of spiders have eight eyes arranged in pairs, but this isn’t always true. Some species of spiders can have no eyes, while others may have up to 12.
Not all spiders have eight eyes though this is the average number. The Sinopoda scurion is a species of Huntsman Spider discovered in a Laotian cave in 2012 and has no eyes since it lives in a dark cave. Meanwhile, the Capponiidae family of spiders usually have only two eyes, and they grow more eyes as they mature.
Spider eyes are always designed for the lifestyle of that spider. While the Sinopoda scurion does not need eyes, Wolf Spider species are usually night hunters, so they have eyes that reflect light, allowing them to hunt in low-light conditions. Jumping Spiders also have eyes designed to allow for depth perception to make more accurate jumps.
Do Tarantulas Have Two Eyes?
There is no tarantula with two eyes. Tarantulas have two large eyes at the front, four smaller eyes underneath, and two additional eyes on the side. In total, tarantulas all have eight eyes that can be found close together.
All tarantulas have eight eyes, but they might be positioned slightly differently across species. True spiders have been found to have up to 12 eyes, and there are also species with no eyes. Spider eyes are evolved to suit the lifestyle of that species. Tarantulas have weaker eyesight since they have specialist hairs allowing them to sense vibrations and sound to detect prey or predators.
Conclusion
Tarantulas have eight eyes, but this isn’t the case for all known spider species on Earth. Spiders have eyes that are specially evolved to suit their lifestyle. For tarantulas, this means they don’t need good eyesight since they have very sensitive hairs that let them feel vibrations and sound. Tarantula eyes aren’t good, but they can see enough to support their other senses.
