Looking for comb jelly facts? Your search ends right here. In this article we intend to give you 40 fascinating comb jelly facts that will take you by surprise. These gelatinous marine creatures are true wonders of Nature’s mystery. Absolutely stunning by looks, these gorgeous sea creatures are dangerous predators that often make use of their rainbow colored lights and their nearly perfectly transparent bodies to trap prey. Let us get into some details to learn more about these stunningly beautiful creatures that roam in the vastness of our oceans and seas.
Cool Comb Jelly Facts: 1-10
1. A comb jelly is not a jelly fish though both have a similar gelatinous appearance. Interestingly, they are not even closely-linked relatives.
2. A comb jelly belongs to the phylum Ctenophora whereas a jelly fish belongs to the phylum Cnidaria.
3. Just like jelly fish, comb jelly is a very ancient animal. According to Smithsonian National Museum of Natural History, comb jelly is at least 500 million years old.
4. The comb jelly is known to have two major layers of cells. The internal cells layers is known as the gastrodermis while the external layer is known as the epidermis.
5. Between the two layers of cells, they also have what is known as mesoderm. The mesoderm has musculature.
6. The gut of the comb jelly is an all-purpose gut which is lined by the gastrodermis. This gut has a single opening which serves for taking in food sources, eliminating the waste by products and even releasing and receiving reproductive cells.
8. These creatures have something called ‘nerve net’. A nerve net is actually a loose nerves network which is present within the cells of epidermis.
9. We know that multicellular organisms have complex nervous systems but in case of comb jellies, their nervous system (the nerve net) is the most elementary form known till date among any multicellular organism.
10. Almost whole of the body of a comb jelly is made up of mesoglea – a gelatinous substance present between the epidermis and gastrodermis.
Cool Comb Jelly Facts: 11-20
11. 95% of comb jellies is actually water. This in turn means that the mesoglea is mostly water. A few nerve cells, muscle cells and structural protein present in the mesoglea make up the internal skeleton of the comb jellies.
12. The question is, ‘why are comb jellies called comb jellies?’ That’s because of numerous fused cilia running across their bodies from top to bottom in eight rows, creating a comb-like appearance.
13. These cilia combs have a very important function. They are the tools used by comb jellies to swim in the water columns of the oceans. This makes them the largest living organism to use cilia for swimming. The only other living organisms to do these include microbes like bacteria.
14. While the primary function of the cilia are to act like oars for propelling the comb jellies through waters, they also have another unique function. The cilia give the comb jellies their rainbow effect.
15. In deep oceans, comb jellies appear glowing with multitude of colors running across their bodies along the cilia rows. Some confuse it as bioluminescence but the truth is that as the cilia move they reflect and scatter light, producing the dance of color or the shimmer.
16. This however does not mean that the comb jellies aren’t bioluminescent. Many of them are! They have protocytes that can be found right underneath the cilia rows. The natural light they produce is usually blue and green, which in turn is refracted by the moving cilia, giving them the appearance of glowing blobs of light drifting through the darkness of ocean waters.
17. Because comb jellies do not have well-defined brain like more complex animals, the nerve net comes to its rescue. This net works as a brain for these animals, allowing them detect changes in the chemistry of water around them.
18. Any changes in the chemical composition of the surrounding water is detected by the nerve net, telling the comb jelly that there is either a food source nearby it is in close proximity with some other animal.
19. Though the nerve net of a comb jelly is very rudimentary by nature, it still has statocysts and ocelli. These are very specialized structures that help the animals to navigate through the oceans.
20. Statocysts are special structures designed to help the comb jellies to understand the direction they are facing, i.e. up or down. In short, statocysts help these animals to balance.
Cool Comb Jelly Facts: 21-30
21. Ocelli on the other hand are very special structures that are designed for helping the comb jellies to detect light. These animals can very well understand if there is light or darkness in their surroundings.
22. As opposed to jellyfish, comb jellies are have fewer species (at least that’s what we know so far). There are over 10,000 different species of jellyfish but for comb jellies, the number of species is estimated to be anywhere between 100 and 150.
23. Not enough information is available about comb jellies but from whatever information has been gathered so far, experts broadly classify these animals into 3 major groups – Cydippids, Beroids and Lobates.
24. Cydippids are a class of comb jellies that are known for having oval or spherical body structures. Their most distinguishing characteristics is the two branched tentacles. Simply put, they have two major tentacles which in turn are fringed with smaller tentacles.
25. Cydippids are equipped with special pouches or sheaths on two sides of their mouths. The job of these pouches is to accommodate or house the tentacles when they are retracted back.
26. Lobates are pretty interesting. They derive their name from the two big lobes right below their mouth. The lobes are more like muscular lips and they house the tentacles in grooves on the inner surface of the lobes.
27. In order to hunt for food, especially plankton, the lobates close around plankton morsels and trap them with their tentacles and push the food towards the mouth.
28. Some of the lobates can actually have cilia right next to their mouth apart from the usual 8 rows of cilia. These cilia near the mouth are meant for creating a water current that guides the food towards the right direction.
29. Finally we have the beroids that do not have tentacles at all. To make up for that, these sac-shaped comb jellies are equipped with a big mouth. The mouth can open wide, really wide to take the prey right into the gut. Once the prey is inside, the mouth seals shut very tightly and then the prey is digested gradually.
30. As far as cydippids are concerned, they use their tentacles to grab prey. Unlike the tentacles of jellyfish, the tentacles of cydippids do not sting. They rather use sticky cells known as colloblasts to catch hold of the prey and pull it towards the mouth.
Cool Comb Jelly Facts: 31-40
31. One of the most interesting comb jelly facts is that they have a wide variety of food on their menu. If they don’t find anything, they will simply prey on their own kind. In short, they will become cannibals if needed.
32. Comb jellies even feed on jellyfish but they usually go for siphonophores, plankton, zooplankton, crustaceans etc. They often also go for small fish.
33. Not only comb jellies are some of the simplest animals that live on earth today, they are also extremely important in history of evolution because they, along with jellyfish, according to scientists, are earliest animals on this planet to evolve with organized tissues – i.e. they have a nervous system, a gastrodermis and epidermis.
34. Not just that both comb jellies and jellyfish were the first animals that started using muscles for swimming instead of just drifting along with waves.
35. Unlike jellyfish that are known to have very complex reproduction system, comb jellies are known to have a very simple reproduction method. Most of the comb jelly species are known to be hermaphroditic. This means that they can act both as males and females.
36. What they do is that they release both eggs as well as sperm cells in water. These cells keep drifting through water until they come in contact with other gametes. Definitely this isn’t the most promising method of finding gametes but comb jellies make up for this low probability by releasing eggs and sperms every single day!
37. Many experts believe that the eggs and sperms from a single comb jelly can fertilize each other – self-fertilization! Because they keep producing eggs and sperms every single day, comb jellies are in need of a constant food supply.
38. In case they fail to get enough food, they will shrink in size and stop producing eggs and sperms until they find enough food source again and once they do, they will grow back in size and start producing gametes.
39. Once the eggs and sperms meet, the embryo is developed into a larva. Interestingly, at the larval stage, the baby just looks like a miniature adult. From there, it is all about growing big.
40. As far as defense mechanism is concerned, comb jellies make use of their bioluminescence. In the face of a threat, experts believe, they flash brightly which startles a potential predator, allowing the comb jellies to escape. However, that’s not their only defense! These animals are great at camouflaging in darkness, because most of them are almost transparent and difficult to see. Some species in greater depths produce red pigment for camouflage. Red is easier to produce compared to black pigment and is basically invisible in darkness of deep seas.
Bonus Comb Jelly Facts:
(i) Some comb jellies that live at the depths greater than 200 meters are red in color because red cannot be seen by predators at that depth.
(ii) Since many comb jellies often eat bioluminescent creatures, they have actually developed a red gut to hide the bright lights of the prey trapped inside their guts. This too is a defensive adaptation to prevent predators from spotting them.
(iii) All comb jellies are carnivores except one order of comb jellies. While all others hunt and eat, comb jellies of the order Platyctenida are known to be parasitic by nature. Platyctenids will usually find and attach to host organisms with almost same color.
(iv) Comb jellies can be found in oceans and seas all over the world. However, they usually prefer warm waters.
(v) Experts believe that comb jellies are capable of reproducing at a very early age and hence, their population can grow very quickly.