Contradictory Organisms (plant/animal strategies that really shouldn't work as well as they do)

Things like pyrophytes/pyrophiles and even animals like the Kirtland’s Warbler which prefer fires seem very backwards to me. It seems like that would be to their disadvantage but they’re doing pretty well with it!
I can only think of fire-related organisms right now, but I’m sure there are plenty of other types of examples out there. Nature strategies that seem like a very bad idea on the surface but end up working out pretty well, I mean.

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That’s the first thing I thought of as well! I don’t see how fires actually benefit an ecosystem but apparently some thrive off fire. You would think it destroys the small saplings and prevents the forest from growing but it must benefit it in the long run. I’m no expert on how this actually works haha

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In contrast to the “normal” reproductive strategy of having specific parts on male and female members, insects like Bed Bugs (Cimex lectularius) use a strategy called traumatic insemination, which is as strange as it sounds.

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That is completely insane and a bit disturbing haha…you learn something new every day!!!

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Fire clears out understory growth and some of the older trees, opening up the canopy for young trees. Fire also triggers seeds of some plants to open. The key is high frequency, low temperature, quick moving fires that don’t sterilize the soil and cause hydrophobic conditions that lead to massive flooding and erosion.

My thought on this topic is specialist bees in arid regions. It seems risky to have all your nests rely on one food source that might not bloom at all in a dry year, but I know they have “strategies” to mitigate some of the risks. It must work, because 30-50% of bees in the Western US are pollen specialists.

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That is so interesting! I never knew that it activated the seeds! Now I can explain it to my mom when she is horrified why we purposely set the forest on fire, it has always completely disturbed her.

Specialist species are interesting to me too. So many specialist species are endangered because they’re losing their food sources, and you would think a species would want to be more of a generalist to ensure their survival, like you said if it’s a bad year. Nature has its ways.

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Another unexpected strategy is sequential hermaphrodism, where fish born with male parts switch to having female parts later in life, this happens in Clownfishes (Amphiprion) for example.

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One way to think about it is that wildfires happen, regardless of what the organisms present would “prefer.” Some organisms have evolved ways to deal with these disruptive events and even to use them for various life history processes (like seed germination). Over generations they might actually come to need disruptive events to persist.

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I can’t speak to the specifics anymore, but years ago I saw a documentary on how fire benefits the land. It was set in Australia. One thing that really stood out to me was that there was a species of bird that would pick up hot embers after a fire and rub it under their wings. I was really really surprised; a theory mentioned by the narrator was that the hot embers destroyed parasites in their feathers.

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Cape fynbos is fire adapted, like other mediterranean climate flora.
It is quite wonderful to see what emerges after fire. Think of bulbs and grass. The seeds and orchids taking the gap when the shrub cover is burnt off. Proteas either resprout or shed seeds to catch the first rain.

Our wild bees have a propolis wall in front of their hive - an actual fire wall made of resins collected by bees.

See the watsonia leaf growing in the days immediately after the fire!

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Specialization as opposed to being a generalist is probably always a risk for any organism, but of course evolution doesn’t plan for the long term, it’s driven by selective pressures in the present. A specialist can do very well over time but is vulnerable to a rapidly changing environment that might not allow adaptation to the new normal. Once they’ve gone down that path there might not be many options to get off it.

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One plant I always find contradictory is Tipularia discolor. Many plants in the temperate zones either have leaves in the summer months and drop them in the winter or have special leaves year round adapted to freezing temperatures. And some have leaves for a short time during the warmer months, for example spring ephemerals grow in forests and have leaves in early spring before the trees grow their leaves and block most light.

However Tipularia discolor grows new leaves in late autumn, keeps them over the winter buried under snow and then they wilt away in spring. It makes no sense at all and yet I find them bloom in the forest right now, so somehow it works out for them :laughing:

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Water dispersal. Logically, you’d expect any plant dipersed by rivers eventually to end up as a strictly coastal species, because rivers don’t generally flow uphill. Each generation further downriver than the last, until there is no more downriver.

And splash cups? That is indeed an extremely short-distance strategy, because how far does a raindrop splash, really? You’d think splash-cup dispersed species would be extremely narrow endemics, spreading at best one raindrop-splash distance per generation.

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Pyrophytes are plants which have adapted to tolerate fire. I read up Pyrophytes on wikipedia. It is mainly plants. There is some research on chemicals in smoke that readily induce some seeds to sprout. These seeds will not sprout well unless there is a fire. As a hobby horticulturalist, I’ve thought about using smoke in water or partial burning of eucalyptus seeds to get them to start growing. I’ve not tried that out yet. Many Eucalyptus species are adapted to full sun. As for birds, there are some small falcons which have learned to hunt insect preys that are flushed out by bush fires. These are not really falcons. I think some species smaller than falcons or shrikes might do that. Seen in a nature documentary.
Kirtland’s Warbler is a rare bird species. In my opinion, it is not a pyrophyte. That species has some peculiar requirements of prefering young pine trees in a large forested area. and it nest near the ground. That will be quite risky, as rats may raid some nests. I do not know, just my guess. They don’t do captive breeding experiments? That might increase the population. It is cool that the scientists are able to revive the population by understanding the behaviour of the species. It is rare probably even before human settlement due to its special requirements. Such small birds generally are able to rebound quickily once people learn more about them.

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Yea, I was referring to the fact that it only lives in jack pine forests, and jack pines are pyrophytes. When the jack pine populations dropped due to the human stopping of wildfires, kirtland’s warbler populations dropped dramatically as well.

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is this really that strange? perhaps I’ve just known about this for a long time, and I’m just used to it, but as a reproductive strategy it makes a lot of sense, by maximising the number of mates a fish can spawn with, creating maximum genetic diversity in it’s offspring. this is actually surprisingly common in coral reef fishes, occurring in clownfishes, wrasses, parrotfishes, lethrinids, marine angelfishes, anthias and groupers, and likely others we don’t know about yet. as for non-coral reef species, it is also documented in Barramundi, swamp eels, sparids and anglerfishes.

there’s a fantastic clip from Blue Planet 2, showing off sequential hermaphrodism in Asian Sheepshead Wrasses (called by their Japanese name, Kobudai, in the documentary). the clip is available on youtube, it’s definitely worth checking out!

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Not strange, just unexpected coming from a plant perspective. With plants, there’s perfect flowers that have both sexed-parts, flowers that are sterile, flowers that are one sex, etc. I’m not aware of a transformative strategy with plants, so it’s a bit mind-blowing to see it in another branch of life.

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Interestingly, in my Ichthyology course years ago, this was discussed in terms of why this occurs only in saltwater fishes. It was related to the kidney – the type of kidney found in saltwater fishes is part of the sex-change process; but switching to freshwater, or to terrestrial life, requires switching to a different kind of kidney, which in turn takes away the ability to change sex. Unfortunately, i can’t seem to find the article.

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Oh huh, very interesting! I wasn’t aware of the reason why no freshwater fish are sequential hermaphrodites.

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