Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[Shoku]

The DNA is different how?

Male and female humans have got 22 chromosomes that have nothing to do with gender. You can mix and match them any way you please so long as we've got the two. For the most part you really just need the one of each but any time you get some fatal flaw on the one the second copy can usually compensate- so throw away more defect babies or carry a backup of the instructions. Plus junk like the immune system variety I went over before and a small number of things that need both copies to balance out.

A third set? Costs a little more to replicate each cell but the third copy comes through to save the day about 10% to 1% as often as the second chromosome would have with just the pair instead of the triplet. Then you need to find a third partner to actually reproduce. No, the cost just doesn't balance out.

Really though I'm rejecting the concept because
A: It's familiar. I've seen people cram more DNA into things in fiction because it's easy to say "you know how we've got two of that? Well they have three."
B: It's a cell biology / chemistry thing. We're working with a different scale here. If you want to do triploid organisms some other time (Maybe on some ten times normal gravity world or with a replacement for water) sure but that's not first run material.

[Supermikhail]

 

Okay, I'll wait for another Ark.

Spoiler (click to show/hide)

The tubes are supposed to come from different balloons when a new Bulbosaurus is formed. So, naturally, as sexually conceived individuals, they would have DNA slightly different. And I'd think it would be somewhat unfair if in one Bulbosaurus three tubes mated in couples, as then there's no assurance that the genes of all three will "live on", and no one actually wants sexual competition inside one creature.

[Shoku]

So is there anything that keeps the tubes safe as they travel to their next, uh, host?
It seems like putting the pricey sexual reproduction bits out in the open water and at a reduced size (and thereby higher chance of death) would be undesirable.
*I'm trying to confirm if this is an area that natural selection would act upon as soon as there were a lot of hungry mouths around.

So, does it really need to be three? I know the bulbosuarus has that sort of symmetry but if the tubes didn't want to take risks they could adopt a shape that "plugged" the narrow point when just two were in. In time the unused cavity might even independently change form for some other use.

[Supermikhail]

Wha? Er. They're like... larvae. Why at a reduced size? Embryos conceived by 3 individuals develop inside the balloon for some time, and by the time they leave they're considerable size and are able to swim pretty fast (except when hindered by the balloon embryo, which is 30% of the time, so I'm thinking that this variety should be somehow be adapted to that).

I accept 2 tubes, but that would eventually make Bulbosaurus bilateral. And I guess it's going to evolve pretty fast, seeing as at first it would be more unstable than the 3-tube species. Gotta think about that.

P.S. To increase survival, maybe the balloon-carrying larvae variety could at first go into the depths where there aren't as many predators as at the surface, and the balloon at some point, when it's sufficiently developed, would produce a lot of gas which would bring the whole creature up, into more densely populated parts.

[Kusgnos]

I haven't read the whole thread yet, but here goes with something. Kinda. If I'm doing it wrong, please tell me. I didn't think up all the evolutionary things that could have led to this creature; I only came up with the idea while doodling. A hermaphroditic small organism that lives in water and is minimally mobile.



1. Adult stage. I know, it looks like some kind of sperm animal. But I figured that if there's plant globs on water surface, it'd be simple in design to get to it by just flailing a flagellum about. I presume it has some sort of rudimentary sensory system based on light or oxygen/carbon dioxide/whatever the atmosphere is for food proximity, and a general desire to avoid rippling water, since stuff that might eat it would make lots of rippling. Mouth is on the underside, and it also passes waste out through that orifice. Has very basic mandibles. More like nubs, I guess, to let it latch onto food a bit better. Tail's important to survival. Without dat flagellum, it'll die.

2. When it has eaten a lot and gorged itself and is still somehow not eaten by a predator, it's time for reproduction! It swims downwards towards...I'm assuming sand or something, underwater, and its tail will detach, since it does attract predators. Wriggling things catch the eye...or the sensory neuron. Catches the something, anyhow.

3. This thing is kind of whitish-dull brown in color. Might look like a pebble. It's also pretty small. I think this part might be a little unrealistic, but the place where its flagellum used to be is also the place where it spews out genetic material. After its little leg nubs dig downwards, it gets comfortable and sticks its genetic material spewer upwards. I think of a sphincterish thing contracting and expanding.

4. It uses all that energy from its gorging on creating little cells that contain genetic material, and spews them out into the water around it. Water currents carry the genetic material around. It stops after a day or so, and chills out.

5. After a few days (probably less than that, come to think of it. This organism shouldn't have such a long lifecycle.), it switches gears and gets back into work. Instead of spewing out, it sucks in. Probably sucks in a bit and vomits it into the sand? Not sure. But the idea is to get genetic material of its species from the water. If it ends up getting its own back, well, it'll just be like asexual reproduction, and kind of like plants self pollinating. If it ends up getting another organism's DNA/RNA (or whatever it is here), it'll be like a sexual reproduction with more genetic variation. Whee.

6. Now it devotes the last of its energy into pumping out little eggs inside of itself. Mixin' up them oocytes with its own genetic material, or maybe with another organism's material. Depends on whether it got lucky, heh. It's self destructive, since trying to fill itself with as much eggs as possible leaves little room for anything else.

7. After it's full enough, this sets off a feedback signal to its nervous system and its outer skin thing layer begins destroying itself very cleanly. Apoptosis or something akin. All the little eggs are released out into the wild, and hopefully some water currents will carry a few of the tiny eggs off someplace else, or maybe its body spasms when it dies and it gets eggs all over the place. Not sure. Either would work.

8. When the little eggs hatch, the little maggotysperm are nearly defenseless. Hopefully several of them will make it past predators and the cruel environment. They're like little white beans with a small, weak tail at the end that twitches and sends them propelling forward in water.

9. I have no idea how it gets enough energy to grow a nice tail. I guess it eats really small things like algae or what passes off as algae, or maybe other animals' wastes that still have a bit of nutrient. Then when it grows big enough like its dadmom, it can find globs of plant matter and devour them, and eventually spew out things and explode its very own little babies. A great life.


Someone who knows a bit more about biology and the like please correct me. Or, if this is just too silly for the project, tell me. It's just a random contribution.

[Shoku]

It wouldn't make it bilateral at all. We've got some very obvious asymmetry with our heart and liver, (and lungs, and appendix, and spleen, and brains...) but look at how bilateral we remain.

Basically the stomach is most of the space in there but does our stomach (another asymmetric organ!) really define all that much of body plan? Not really, it just fits in with the other organs.

-

Actually I was thinking it looked like a free floating brain and spinal cord.
Well it's surprising how present food is everywhere. Sea cucumbers actually just eat sand and digest the bacteria on it.

My one gripe about this is the one size fits all thinking about the predators. We don't have anything with precise senses so the camouflage and tail loss for stealth purposes aren't applicable, yet.
I'd like to know more about the mouth, and maybe if there's any reason the young don't leave through the hole left by the tail/used to suck in water.

[Supermikhail]

Hueg post.

Notes on visual presentation. With posts like this, it's a very good idea to put illustrations next to respective stage explanations. Makes it much easier to follow.
Also, the way the stages are depicted moving or "aimed" counter-clockwise, and the cycle actually going clockwise, is counter-intuitive and confusing.

-

Shoku, the tubes kind of define the face of Bulbosaurus. Our face is bilateral. That's how I figure that. That is, the tubes aren't only inside, they go outside, too.

[Shoku]

Face? It has a mouth and no sensory organs.
~How can you say it has a face~

It doesn't sound like you've said anything about them being involved in eating and they even seem to leave given that we have an empty one at the start and them attaching in the final panel.

[Supermikhail]

Oh. My bad. When I was drawing the first panel, I intended it to be about evolution. So, the first panel is kind of irrelevant. The tubes don't leave, ever, the only time the balloon goes without a tube is before they are united when they leave their parent.

Well, it's not a face, but they still go outside, and what we have outside, usually, is bilateral.

[Shoku]

Only when there's not a reason for it to be different. Narwhals grow that one spiral horn thing out of just one side of their mouth. Most of the crustaceans with claws have a recognizable difference between those claws (one is for crushing...)

Why do they go outside though? If the fusion actually taps into the tissue of the balloon they could get food there and if not they would have their faces positioned just fine to gobble up what the balloon had just swallowed. Plus they obviously have all of the mating go on inside of it, as per your picture.

[Supermikhail]

Well, they are supposed to clean up the inside of the balloon and release the refuse outside... Er. I can't visualise that myself. Do you think it would work? I actually suspect that having three/two tubes protrude outside of one's mouth doesn't help biting on food.

[Shoku]

There is one alternative though: they could take over eating. At first they would probably just be a sort of parasite using the balloon like a nice little cave where they were unlikely to be eaten but their new shell would be ephemeral. Leaking nutrients into it would make it last longer so there could be some mix of conditions where that was actually advantageous in a gradual evolutionary way though this is still quite improbable. Sounding much more reasonable comes the idea that these do not eat the same foodstuff but that the tube swallows things regardless and just passes the inedible ones out some opening near its backside. This would probably still ultimately shorten the lifespan of the larger creature but if the reproductive relationship you've thought of gave its young significantly improved survival and eventually reproduction themselves it might still be an advantage.

Now, the internal cavity itself need not have particular lobes for the tubes to attach to. A parasite would probably just line itself up with the end sticking out and then attach wherever it happened to lay. Later along in the relationship the whole digestive system of the balloon could go through some reduction because it was just having it's foodstuffs hand picked for it and receiving any other waste from the tubes- except at the deep end rather than so much at the front. It would be best to reverse the direction of any specialized tissues of concentrations thereof. As such with the mouth end basically having waste pile up around it they might develop an exit, albeit one that the tubes wouldn't be compatible with. It wouldn't want to let some greedy(er) third party just come along and plug it up for mating privileges. A slit seems like it would be a good deterrent compared to the round opening and eventually it might have patches of flesh that were more or less desirable points for attachment, so as to steer the tubes away from the anal slits.

You like?

Edit: I was looking through this old thing again
http://www.talkorigins.org/faqs/comdesc/phylo.html
and noticed that it had very nice trees. I would most prefer to do the ones for this project like the first image, with characteristics placed on the branches prior to splits. Seeing as we have the exact species at each node it would be much more picture cluttered though. We'd have to do the pseudo timeline to get away from that, though that would mean wiping the slate clean and really starting over, which should come after the jellyfish exercise.

[Supermikhail]

Yeah, the tubes are supposed to eat what the balloon finds unsavoury. And I guess right now this could use some divergence (one creature has no symbionts, one creature suffers from parasites and deals with the problem somehow, one creature has 2 symbionts, and one creature has 3 symbionts, and those are arranged somehow), and 3d visualisation, as I'm having trouble visualising all that in my head, and especially working with visualisations. Unfortunately, it is programming season for me.

And phylogeny trees could be useful, too.

[Shoku]

As for parasites there could be one where they don't poke out but just pick and choose from what the balloon swallowed up.

See how easy it is to make variations when you've got two things that you can just shift in relation to each other? Now let's try to make an animal with that much detail!
Oh right, the jellyfish thing...

[Supermikhail]

Unfortunately, due to recent self-inflicted sleep deprivation... the progress towards the ultimate knowledge has been rather slow.

Hey, what do you know, flip a page and it's Cnidaria. Wikipedia says jellyfish are there. However, the section is another hundred pages.