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Carapacers, as a group, severely depend on vanadium, as their blood pigment is vanadium-based. There is no viable source of vanadium on land at present, so unless we do some funky soil color retcon to make Dixon and Talon weirdly rich in vanadium, that means saycers, which are freshwater, have a bit of a problem. I had actually intended to abandon the freshwater line to extinction after discovering this issue right after riversaycer was approved and wish I had brought it up at the time; as it is right now, carapacers should be restricted to saltwater without heavy justification. So what do we do about the saycers?

An unrelated saycer problem also related to their blood, I did not notice at the time that Sealsaycer evolved lungs derived from its stomach. If I had, I would have rejected it, as its digestive and circulatory system are the same organ and this is just asking for lungfuls of acidic blood. That detail should probably be revised or removed.

Is there a way it can extract oxygen from air through a specific chamber in its stomach, even if the breathing chamber is full of watery acids, rather than air?

As for the fate of the Saycers...well, either they get retconned into extinction, or one could find commonalities in saycers' diets and then say that diet commonality is oddly high in vanadium.

QUOTE (Coolsteph @ May 20 2021, 11:20 PM)

Is there a way it can extract oxygen from air through a specific chamber in its stomach, even if the breathing chamber is full of watery acids, rather than air? As for the fate of the Saycers...well, either they get retconned into extinction, or one could find commonalities in saycers' diets and then say that diet commonality is oddly high in vanadium.

That sounds like it would be significantly less effective than my suggestion over private messages of modifying the gills to hold water.

If a food source is made vanadium-rich, then the question becomes, where did that food source get it?

If the issue isn't resolved, I can make a minor plague that plausibly removes the freshwater species. There will be a gen or so to save saycers by making saltwater species (and I plan to do this anyway), as it would be descended from a less deadly disease I'm working on affecting carapacers in general.

That's a good point about the food sources. If migratory ocean-to-freshwater species can't bring in enough vanadium, a minor plague would be best.

I intended to give the Sealsaycer a unique way of breathing inspired by air-breathing fish, namely the air-breathing catfish. Is it possible to allow it to breathe from air using some kind of buccal or esophagal pouch? If not, would some kind of primitive labyrinth organ-esque structure derived from extra "neck-ribs" (gill arch-esque structures---its ancestor doesn't seem to have bony gill arches) work? The fact it lives in a river, which is probably oxygen-rich, should allow it to plausibly compensate for any inefficiencies inherent to just evolving the trait.

P.S. I'm still on vacation, so my activity will be sporadic.

This post has been edited by Coolsteph: May 24 2021, 04:42 PM

Not sure if this helps, but maybe some of these links might be useful:

"The best food sources of vanadium are mushrooms, shellfish, black pepper, parsley, dill weed, beer, wine, grain and grain products, and artificially sweetened drinks. Vanadium exists in several forms, including vandal sulfate and vanadate."


https://www.researchgate.net/publication/28...ushroom_species

https://pubs.rsc.org/en/content/articlehtml...3/dt/c3dt50525a

https://en.wikipedia.org/wiki/Amavadin

This post has been edited by Nergali: Jun 26 2021, 09:39 PM

So we had discussed this in the discord awhile ago, as I have been working on a sealsaycer descendent for months, which would be moving to a more terrestrial life. To deal with vanadium issue, the plan was to set up the cycle through other species. Vanadium uptake from the soils could be done via microbes involved in the nitrogen cycle, operating much like azorbacter which utilizes a vanadium based nitrogenase in certain conditions. From there, uptake by flora would further accumulate the vanadium. Certain mushrooms are the best examples of this utilizing vanadium compounds as toxins or peroxides. This would provide a vanadium source on land that the saycers could make use of.

This cycle alone would most likely not be enough to support fully terrestrial fauna over a certain size, the specifics of that limit depend on how much can be accumulated in the flora and used by the fauna, so lots of math. But the main limiter would be the lack of a vanadium cycle from the sea to the land. A cycle like that would need to be created via oceanic fauna traveling into freshwater and bringing the vanadium with them, basically the same as salmon runs fertilizing the forests around their rivers.

Until such a cycle can be developed, I do agree on the restriction to saltwater. The sealsaycer Evo I had planned can easily be shifted to an amphibious species inhabiting coastal waters and beaches, provided the respiration issues with sealsaycer are fixed.

So, where do we stand on this? Has a rework of Sealsaycer been developed to fix its internal organ issues? I have a descendent nearly complete for it and its already been modified to a semi-aquatic coastal lifestyle so as to avoid the vanadium issue. So all I am waiting on is the internal rework for sealsaycers organ systems.