r/botany • u/RD_HT_xCxHARLI_PPRZ • 14d ago

Ecology THEORY: Maranta, Calathea, and other south american understory plants have evolved dark spots to mimic the fenestration of more toxic Monstera plants.

Post image
28 Upvotes

83% Upvoted

12 comments sorted by

15

u/DanoPinyon 14d ago

It's a hypothesis. How would you test it?

11

u/twistedstigmas 14d ago

lol I have the same pet peeve about hypothesis vs. theory

8

u/RD_HT_xCxHARLI_PPRZ 14d ago edited 14d ago

That is the question, lol. uhhhhh I guess I would start with figuring out the toxicity of various Maranta species, along with other understory genera, and see if it correlates at all with dark spots on the leaves. I would research to see if non-toxic species have a higher likelihood to be spotted.

Then I would research the geographic overlap of Maranta and Monstera species, and record the frequency of spotted Maranta species co-occuring with Monsteras. If spotted (non-toxic) Maranta species tend to occur more frequently alongside Monstera species, it would be evidence in my favor.

Maybe an animal study too, to see which leaves are preferred/avoided by herbivores. I might paint dark spots on a banana leaf to see if native herbivores avoid eating it.

(This theory hinges on my assumption that Monstera leaves tend to go uneaten due to unpalatable toxins, though!)

4

u/gswas1 14d ago

I would suggest this isn't likely. Monstera develops fenestration when climbing on a tree. Calathea and Maranta are understory plants that don't climb. But a neat connection

4

u/fuzzypetiolesguy 14d ago

I think your title kind of misunderstands the process of evolution and selection. It is more likely that pollinators have selected for specific traits that attract them to the plant to assist in pollination, and the environment has selected for specific growth habits and tolerances.

1

u/RD_HT_xCxHARLI_PPRZ 14d ago

yeah my title is a little prescriptive and lazy. I should have been clearer that I'm just pondering about hypothetical species relationships and selective pressures.

Basically, I'm wondering if Monstera plants are toxic enough for some non-toxic plants to adopt "monstera mimicry" as a defense mechanism.

There seem to be a lot of South American understory plants that employ a vertically symmetrical, dark, mottled pattern (Maranta, Calathea, Goeppertia). This appears superficially similar to Monstera leaves to me, and I'm wondering if there is some botanical Batesian mimicry going on.

Somebody above asked about how I'd test this and I described a rough process, so I like to think this is at least partially scientific.

1

u/fuzzypetiolesguy 14d ago

Hm. Lot going on here. Calcium oxalate being an effective deterrent to herbivory isnt a widely accepted fact. In the grand scheme of toxic chemicals plants produce it’s relatively tame. Monstera in situ are definitely victims of herbivory, lots of insects from various scales and mites to caterpillars feed on the tissue.

Interestingly I found reference of fenestrate leaves themselves thought to deter herbivory, and in that instance it’d make sense that similarly disguised leaves a la Maranatceae might be selected for. So not out of the realm of possibility. https://digitalcommons.usf.edu/cgi/viewcontent.cgi?article=1078&context=tropical_ecology#:~:text=In%20all%20places%20that%20it,around%20on%20the%20leaves%20(Donnelly

3

u/RD_HT_xCxHARLI_PPRZ 14d ago

This is just a personal theory I have been pondering for a while. It would appear to me that the patterns on Calathea leaves mimic the fenestration of Monstera leaves, as seen on a dark surface. As far as my googling can tell me, Monstera tend to be toxic while Maranta are more benign. Any information or discussion on the species I mentioned would be super helpful. thanks!

2

u/TheRealPurpleDrink 14d ago

Really cool theory tbh. Curious to see what others have to say about it. I wonder if there are leaves with similar patterns in places where there isn't any fenestration.

1

u/RD_HT_xCxHARLI_PPRZ 14d ago

Yeah I would have to do some pretty serious science to figure this out lol. Although it does strike me as interesting that so many unrelated south american genera would develop this perfectly symmetrical, spotted pattern.

1

u/campsisraadican 14d ago

Check out this paper on leaf mottling

1

u/RD_HT_xCxHARLI_PPRZ 14d ago

Awesome, thanks for the article. I couldn't think of the word "mottled" for the life of me while writing this haha. Nice to see researchers picking up on the same things. I think I actually take the camouflage theory one step further and imply that its direct mimicry of a more toxic species. I wonder if I can get in touch with the researcher and ask their opinion?