Plants room Not Animals and Animals are Not Plants, Right? Wrong! small Creatures in the Ocean deserve to Be Both at Once!

Authors and also reviewers

I research algae since I hope what we space doing provides a difference in the world. This are certainly interesting time to be an ecologist examining water quality. Phytoplankton blooms are increasingly everywhere, and nutrient pollution and eutrophication space increasing. It used to be complicated to explain what i studied to my non-scientists friends and relatives; now, they review the headlines that water high quality issues and also algal blooms frequently. I examine algae all approximately the world, indigenous Chesapeake Bay come Florida, and also from Europe come China! *glibert

Aditee Mitra

Aditee Mitra

i have constantly thrived on challenges—doing miscellaneous new, finding something different—that is why ns love working on mixotrophs! Our research findings revealed the the mixoplankton actually dominance our oceans. Mixotrophs room not just cool, but fun to study!


Kevin J. Flynn
Kevin J. Flynn

as soon as I was examining for my Ph.D., i wrote computer system games because that fun. Now, rather of aliens battling the out against each other, I use that ability to write computer system simulations of different plankton “fighting” because that life! I uncovered out that you learn quickly when having actually fun and also building and also playing with simulations that plankton is a good way to find out just how nature works!

every Juel Hansen
every Juel Hansen

ns am an experimental biologist that study exactly how plankton organisms communicate with every other and how they interact with the environment. Ns am an especially interested in just how harmful algal blooms develop and also how bloom-forming toxic algae use their toxins to kill and also eat other organisms to get rid of competitors and also enemies. I occupational in the Arctic waters of Greenland, warm waters in northern Europe and also in tropic waters in Asia.

Hae Jin Jeong
Hae Jin Jeong

ns am an extremely interested in resolving harmful algal blooms (HABs), one of the biggest troubles at sea. I have developed several techniques of eliminating HAB types using mass-cultured predators and some effective chemicals. However, ns realized that part HAB types have genomes up to 90 times larger than mine, and I established that i must end up being their friend and also understand your minds. Now I try to emphasis on converting “harmful” birds to “useful” birds for humans. For fun I prefer to draw cartoons and also make jokes!

Diane Stoecker
Diane Stoecker

I research plankton since they space beautiful, live in the sea, and because there are many varieties that us know little about. I choose to walk to sea to perform research and also to occupational with cultures in the laboratory. Do discoveries around tiny plankton has actually been fun and has allowed me to occupational with scientists in countless countries.

Young Reviewers

Age: 11

My favourite hobby is drawing, I deserve to draw nearly any character from movie or video clip games, I also like to create brand-new characters and write new stories. I exercise American Football due to the fact that I to be 7 year old, this year I will play my fifth season, and also my position is Center.

Age: 8

My favorite hobby is the computer I prefer to research everything; I additionally like to play Minecraft. I love creating brand-new worlds, I have dozens that them. I would love come travel around the world and also meet remarkable people and also places. I exercise American Football due to the fact that I to be 5 year old, this year I will certainly play my fifth season, and my place in the offense is Center and in defense is sleep Tackle.


On land, plants do their own food by photosynthesis and also animals live through eating. However, in the microscopic people in the oceans, that is not that simple. Many microscopic so-called plants (phytoplankton) can likewise eat choose animals and also many microscopic so-called animals (microzooplankton) can likewise photosynthesize favor plants! an ext amazingly, few of these microzooplankton eat tiny phytoplankton and also continue come live off photosynthesis from those ingested phytoplankton. These organisms acting prefer both plants and animals are dubbed mixotrophs due to the fact that they mix (combine) various ways of obtaining nutrition. This fascinating creatures space not rare freaks the nature, yet are an extremely common. Some mixotrophs are an excellent food for fish, while others make poisons that can get into ours seafood and even kill fish. Some are enhancing in coastal waters because of pollution. We room learning just how important mixotrophs room to s ecosystems.

You are watching: What can plants do that animals cannot

One of the most simple “laws” of scientific research is that plants space plants and animals room animals. Right? that course! Plants room green. Lock live making use of sunlight, carbon dioxide, and nutrients, do their own food v the process of photosynthesis. In contrast, animals live by eating various other organisms (plants, animals, bacteria, or also bits and pieces the dead organisms). Is this “law” of science correct? not always! Going against this “law” are oceans full of microscopic organisms that deserve to be both plant-like and animal-like at the exact same time! castle photosynthesize and also eat.

Have you ever before heard of a plant that have the right to eat an animal? There are a few land plants that eat insects. The most commonly known example is the Venus flytrap, which records insects top top its unique leaves and also then digests castle (Figure 1A). Together land plants are taken into consideration a bit of a freak that nature. In the ocean, however, these freaks are not freaks at all; they room actually very common. You have the right to find plenty of of these kinds of biology if you look under the microscope and explore the microbial plankton, the tiny organisms the live in the water world. Not only are over there plants the eat, there are animals that photosynthesize! these fascinating, mixed methods of getting and making food are dubbed mixotrophy and also the biology that carry out mixotrophy are called mixotrophs (meaning blended nutrition). A non-science term for these organisms could be “plantimals,” due to the fact that they have the right to be part-plant, part-animal (Figure 1).

Figure 1 - (A) Cartoons of a hungry plant photosynthesizing (left) and also eating (right).(B) The Venus flytrap plant both photosynthesizes and also eats insects. Cartoon by H. J. Jeong, photos from Shutterstock.

Planktonic Plants the Are also Animals

Phytoplankton room microscopic plant-like organisms the live in the water. Their surname tells us that lock live on irradiate (phyto) and drift with the water (plankton). Every fall of water normally consists of hundreds of hundreds of these tiny, single-celled organisms. Phytoplankton are natural and important; they develop 50% that the oxygen in the air us breathe, and they are additionally food because that fish and also other pets in the ocean. Over there are numerous hundreds the different species of phytoplankton. Because that decades, most scientists have thought that phytoplankton lived just by photosynthesis. It transforms out that plenty of of these phytoplankton additionally eat the method animals do <1>. Part eat various other phytoplankton, part eat bacteria, and some eat tiny pets (Figure 2). Few of these mixotroph phytoplankton eat just reluctantly or rarely. Some space aggressive and also can stuff themselves full of food! this mixotrophs thrive much quicker when they can eat and also photosynthesize at the exact same time, contrasted with once they flourish by photosynthesis alone.

Figure 2 - (A) Cartoons of microscope phytoplankton dubbed mixotrophs.

The ways the mixotrophic phytoplankton eat deserve to be nice gruesome. Part gobble up whole organisms, while some harpoon your food and suck the end the innards making use of a self-made straw. Some have the right to make their enjoy the meal explode, leaving a nutritious soup that they can soak up. Part can even eat various other organisms the are lot bigger than themselves. Part mixotrophic phytoplankton usage poisons to death what they want to eat. Interestingly, some can make these poisons only once they photosynthesize and also eat at the very same time. An instance is an organism dubbed Karlodinium. Karlodinium eats other small algae aggressively, but it appears to only eat throughout daylight. Why does it not likewise eat at night? It turns out the Karlodinium provides the gift compound that it release to kill its food during daytime, when it is additionally photosynthesizing.

Planktonic animals That Are additionally Plants

Along v phytoplankton, there room other, tiny animal-like biology in the ocean that are dubbed microzooplankton, because they are tiny (micro-), pet (zoo-)-like plankton. Microzooplankton eat too many of different things, but when they eat small phytoplankton, they can end up being part-time plants. How have the right to they carry out this? One form of microzooplankton eats phytoplankton, yet they perform not digest the photosynthesizing machine (the chloroplasts; number 3). They keep the stolen chloroplasts and also use this to photosynthesize! deserve to you imagine the broccoli friend eat continuing to photoyynthesize in her stomach after friend ate it? various other “animal” mixotrophs eat many phytoplankton however do no digest them at all–they keep the intact phytoplankton within your bodies and also drift in the seas like microscopic greenhouses; lock live turn off the photosynthesis from the still-growing phytoplankton castle ate.

Figure 3 - (A) Cartoons of a hungry microzooplankton (left panel), eating little phytoplankton (middle panel), then capturing sunlight for photosynthesis, using the phytoplankton chloroplasts now inside its human body (right panel).

Some mixotrophic microzooplankton are picky eaters, and also become plant-like only by eating their favorite foods. One form of these stroller, stick mixotrophs is a varieties called Dinophysis, i beg your pardon is uncovered in oceans all over the world. Dinophysis wants chloroplasts indigenous one specific form of microscope phytoplankton however cannot eat those phytoplankton directly. Therefore Dinophysis eats an additional mixotroph named Mesodinium the eats the certain phytoplankton with those chloroplasts. The Dinophysis then pokes a hole right into the Mesodinium and also sucks all their guts out to ultimately get the chloroplasts that wants.

Talk about gruesome, picky eaters! that is actual microbial war in the oceans!

Where space Mixotrophic Plankton uncovered in the Oceans?

All our seas are residence to mixotrophic plankton, however different varieties live in different parts of the s or at different times that year. Some types, such together the Karlodinium, are mainly found along coastal areas, if other types are an ext common in the open waters that the oceans. Other types of mixotrophic plankton are linked with polar waters or tropic waters. Some are more common during specific seasons—especially summer.

Many mixotrophs grow really well in waters the have become eutrophic (enriched v too plenty of nutrients or fertilizers) from all of our human wastes <4>. Once we apply fertilizers come lawns or farm yard land, not every one of that fertilizer is provided by grass or by crops. Several of the fertilizers room washed out to sea after the rains. This fertilizers climate feed the phytoplankton in the ocean water, which climate grow, ending up being food for other plankton, including the mixotrophs. With more food, mixotrophs deserve to grow an ext and more. As soon as phytoplankton, including those that are mixotrophs, flourish in large numbers the is called a bloom.

Why have to We be Interested in Mixotrophs?

Mixotrophy is now considered so necessary in the plankton communities that it has actually been proclaimed as among the recent revolutions/discoveries in scientific research that could adjust everything (Scientific American Vol. 27, No. 3, July 2018)! Mixotrophy alters the means we think about all facets of life under the water <1>. Plankton life walk not fall neatly into plant and also animal categories, as does life top top land. In the human being of plankton, there is still much that we carry out not know or understand. Together scientists, that is really cool to shot to number out how mixotrophs work! over there are limitless numbers of inquiries that we have and also important topics that have the right to be explored through these amazing little creatures <5>.

Scientists space also very interested in mixotrophic plankton since they ultimately sustain all the other organisms in the ocean, indigenous oysters and crabs to fish. With climate change, we additionally want to know exactly how organisms in the oceans, consisting of mixotrophs, are transforming and how that may adjust the populations of fish that human beings use because that food <1>.

Many the the plant-like mixotrophs can harm other types of organisms, consisting of whales, dolphins, or turtles. Figuring out how mixotrophs influence these larger organisms is necessary if we desire to protect those important creatures. The day-time eater Karlodinium deserve to release few of its poisons into the water, destroying the gills of fish, which death the fish practically immediately. Karlodinium climate eat bits that fish for your dinner. Others, such together Karenia brevis turn off the shore of Florida, develop a poisonous compound that might not just kill fish, however is strong enough to kill even vast manatees! In the summer of 2018, Karenia brevis blooms resulted in large fish kills off the Florida coast; countless sick and dead pets washed ashore, including over 100 manatees and also 300 turtles. This was a disastrous loss of marine life and additionally made the beaches slimy and smelly.

Scientists are particularly interested in mixotrophs that make poisonous compound that can make human being sick. If us eat mussels that fed ~ above Dinophysis, the picky-eater-mixotroph mentioned above, we can obtain diarrhetic shellfish poisoning; this means that world get uncomfortable stomachs and also have diarrhea. The toxicity compound make by Karenia brevis can get carried in sea spray and makes united state cough if us breathe the air at the beach. The types of toxicity compounds made by various mixotrophs are very diverse and also there is much we still execute not know around the chemistry of this compounds. We are an extremely interested in knowledge what we can do to prevent these tiny, toxicity organisms from cultivation out of control and also how we have the right to keep people from obtaining sick.

These exceptional mixotrophs, v their fascinating diversity, are absolutely shaping our oceans and also the food we get from it. It may seem to it is in a mixed-up people of microbes in our oceans, yet they are significant players on ours planet. Therefore, they room worthy of our attention. Scientists, fishermen, seafood lovers, coast goers, environmentalists, and all citizens of the planet have to care around what lives and also grows in our oceans!

For more information on mixotrophs


Photosynthesis: The process by which environment-friendly plants and also plant-like algae use sunlight, together with carbon dioxide and water, to make their very own food.

Plankton/Phytoplankton/Microzooplankton: Plankton space drifting or floating biology in the sea or in freshwater. Most are microscopic. As soon as plant-like, they are dubbed phytoplankton, and also when animal-like, lock are called zooplankton. Small-sized zooplankton room termed microzooplankton.

Mixotrophy/Mixotroph: Mixotrophy is the procedure of combining photosynthesis (like a plant) and feeding (like one animal) in one organism. A mixotroph is one organism the combines that nutrition in this way.

Chloroplast: Photosynthesizing apparatus in plants and also marine phytoplankton.

Eutrophication: The process of enriching a human body of water v nutrients. Eutrophication can an outcome in harmful algal blooms or other negative effects ~ above the ecosystem.

Conflict of attention Statement

The writer declare that the research was conducted in the lack of any commercial or financial relationships that can be construed as a potential problem of interest.


The authors obtained support indigenous the adhering to agencies for their occupational on mixotrophy: the US nationwide Oceanic and also Atmospheric administration National Centers for coastal Ocean scientific research Competitive Research regimen under compensation No. NA17NOS4780180 (PG), the european Commission’s Horizon 2020 Research and also Innovation Programme under the Marie Skłodowska-Curie MixITiN grant covenant No 766327 (AM, KF, and also PH), a grant (no. 4181-00484) indigenous the Danish research Council for Independent research (PH), and also the helpful Dinoflagellate regimen of Korea institute of maritime Science and modern technology Promotion (HJ). The authors give thanks to Rohan Mitra-Flynn for helpful comments top top this paper. This is contribution number 5535 native the college of Maryland facility for environmental Science and ECO933 from the NOAA ECOHAB Program.


<1> Mitra, A. 2016. Uncovered: The secret Killer Triffids That overcome Life in our Oceans. The Conversation.

See more: The Serous Membrane That Covers The Lungs Is The Human Body, Anatomy, Thorax, Lung Pleura And Mediastinum

<2> Stoecker, D. K., Tillmann, U., and also Granéli, E. 2006. “Phagotrophy in harmful algae,” in Ecology the Harmful Algae, eds E. Granéli, and J. Turner (Springer: The Netherlands), 177–87.

<3> Park M. G., Kim, S., Kim, H. S., Myung, G., Kang, Y. G., Yih, W. 2006. Very first successful culture of the naval dinoflagellate Dinophysis acuminata. Aquat. Microb. Ecol. 45:101–6. Doi: 10.3354/ame045101

<4> Burkholder, J. M., Glibert, P. M., and also Skelton, H. M. 2008. Mixotrophy, a significant mode that nutrition because that harmful algal types in eutrophic waters. Harmful birds 8:77–93. Doi: 10.1016/j.hal.2008.08.010

<5> Flynn, K. J., Stoecker, D. K., Mitra, A., Raven, J. A., Glibert, P. M. Hansen, P. J., et al. 2013. Misuse that the phytoplankton-zooplankton dichotomy: the must assign organisms together mixotrophs in ~ plankton useful types. J. Plankton Res. 35:3–11. Doi: 10.1093/plankt/fbs062