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Plants and animals are easy to tell apart. This is a plant and this is an animal -- but
THIS is BOTH!
Hey animals and nearby listening plants, Trace here for DNews, thanks for tuning in!
If you look back to middle school science, you might remember Kingdom, Phylum, Class,
Order, Family, Genus, Species. Easy to remember because, Kids Playing Chicken on Freeways
Get Smashed. Kingdom has five groups, Monera, Protista, Fungi, Plante, Animalia, but it
was invented by humans, so sometimes there are exceptions to every rule. To be a plant,
an organism has to make it's own food and have cell walls. To be an animal you acquire
nutrients by ingestion and don't have cell walls. There's more to it, but that's the
basic distinction. This distinction goes even deeper.
As biologists have looked into the genes that make up the DNA of our planet's organisms,
classification has gotten... *eeeahhhhh* let's just say fuzzy. In this case, two studies
published in the journal Genome Research describe the way microRNA affects plants and animals
differently. Animals, like humans, have microRNA which float around the cell nucleus activating
and deactivating genes. It's a little technical on HOW, but in essence: animal microRNA affects
how DNA and RNA express genes. This helps organisms adapt to changing diets, environmental
stimuli and so on. Though, while animal microRNA affects lots of different gene expressions,
plant RNA is far more specific.
The sea anemone is classified as an animal, because its DNA is similar to a vertebrate,
it gathers food and does not have a cell wall, but its microRNA behaves as a plant! Go home
nature, you're drunk.
This isn't the only Plantimal out there that gives the biologists a nerdgasm // Plantimal!
It's a thing now, I want all the credits // A 2007 study from University Of Kalmar in Sweden
found some species of algae which were plantimals ... they dubbed them mixotrophs because they
can produce energy from sunlight, like a plant, but they EAT other things, like an ANIMAL!
Another is the Mesodinium chamaeleon which sounds like a fancy lizard, but it's actually
a single-celled organism. It EATS OTHER THINGS -- so animal -- but it can use the things
it's eaten and live off THEIR photosynthesis while it's inside its body -- until the prey
is digested. Presumably that's why it's called a chameleon, because depending on whether
it's eaten green or red algae it will change color.
The process of eating something and using it, evolved 2 BILLION years ago. It's called
endosymbiosis. When the first single celled animals ate bacterium, the prey cell became
part of the predator cell -- this is how we got mitochondria! Many single-celled organisms
flirt with the animal-plant boundary line depending on their needs and adaptations...
biologists are total frenemies with them... remember frenemies? Haha, so dumb.
The sea anemone is significant, because it's multi-cellular, and the gene regulation is
similar to that of a fruit fly, which means there's likely a common link between human,
fly and sea anemone 600 million years ago.
I think maybe plants and animals are part of a thinner line... like fruits and vegetables...
what do you think?
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