Jellyfish, which have umbrella-shaped bells and trailing tentacles, are mostly free-swimming marine species. These aquatic creatures can be found in all types of ocean water, but they prefer warm tropical and cold arctic waters.
These animals aren’t fish at all; they’re invertebrates because they don’t have any bones. Furthermore, jellyfish lack brains, cores, lungs, and even eyes.
Despite having a primitive body, they have survived for millions of years. In fact, jellyfish are thought to be the world’s oldest multicellular species as they’ve existed since dinosaurs roamed the earth.
There are over 2,000 different species of jellyfish that we are aware of. Only 70 people are capable of harming others.
Despite this, scientists estimate that about 300,000 separate jellyfish species have yet to be found. It’s important to keep in mind that more than 80% of the ocean has yet to be explored.
Jellyfish come in an extensive range of sizes due to a large number of species. The smallest species has a diameter of 1 millimeter, while the largest has a diameter of 2 meters and tentacles as long as 60 meters.
Kindly read further to find out more about jellyfish, their diet, and hunting techniques.
What do jellyfish eat?
Jellyfish are mostly carnivorous creatures that feed on small fish, copepods, fish eggs, and plants. Some jellyfish species can consume smaller jellyfish as well. Jellyfish hunt by paralyzing their prey with stinging cells in their tentacles before swallowing them.
Their mouth has an opening inside their bell-shaped body. They eat and throw waste out of this hole.
How do jellyfish hunt?
What is the best way for a brainless sea creature to hunt its prey? Let’s take a closer look at how jellyfish prey. The sensory receptors in their bell and tentacles are the first and most essential components.
When jellyfish come into contact with their food, the tentacles and toxins in their tentacles are activated. Accidents with these animals are normal because they are unable to distinguish between humans and possible prey.
They release toxins through specialized cells that can release venom, paralyzing their prey after finding it and capturing it with their tentacles. Once their victim is paralyzed, they use their tentacles to slowly carry it to their mouths and begin digesting it with their digestive enzymes.
Jellyfish are opportunistic animals because they can eat vast amounts of food by swimming or being dragged around by ocean currents.
Nevertheless, like other species, jellyfish still have several hunting mechanisms:
- Cruising hunting: A characteristic of the jellyfish of the order Rhizostomea; this is when jellyfish catch their prey by cruising. Because of the ocean currents and the jellyfish’s passage through the umbella, their prey is drawn directly to the jellyfish’s mouth. The jellyfish will use their tentacles to capture and consume them at this stage.
- Ambush hunting: It is a form of hunting practiced by jellyfish with longer and stronger tentacles, and it involves swimming in a zig-zag pattern to group their prey and then capture them with fast movements.
How do jellyfish digest their prey?
Jellyfish, despite their primitive organism, are capable of performing essential functions such as food digestion. The mouth of these fascinating creatures is the only cavity they have preceded by the gastrovascular cavity.
Hair cells and digestive enzymes help to break down food in this cavity.
Also, since jellyfish lack a well-differentiated digestive and excretory system, this cavity serves as a system for distributing all nutrients, oxygen.
As a result, jellyfish use the same cavity to both feed and remove waste.
Fun facts on jellyfish
- Jellyfish lack brains, cores, skin, and lungs.
- Jellyfish are the world’s oldest multicellular animals, and they can clone themselves.
- They have teeth in some cases.
- Jellyfish never get entwined
- They come in a variety of colors.
- Jellyfish are almost entirely made up of water.
- Jellyfish aren’t the same as fish.
- There are over 25 different edible jellyfish species.
- Some jellyfish are bioluminescent, which means they glow in the dark.