Planet Four Talk

Spiders and SPLD's (or not).

  • Kitharode by Kitharode moderator

    Do the South Polar Layered Deposits (SPLD), and other such layers, play an important role in determining which 'species' of spiders will form there, to the extent that there is a significant difference in spider morphology between SPLD and non-SPLD areas?

    If the answer is already 'out there' then it'd be good to know. It'll save me a job. The 'other such layers' are part of a gut-feeling idea I'm working on. Such layers can be found outside the SPLD's, on crater floors where material collects as a layer, for example. Also the floors in the enclosed zones of Inca City would qualify. I'm seeing examples of this type of 'layered deposit' with spiders, but there are no spiders around or outside of the layered area.

    My gut feeling is that certain types of layering outside the SPLD's produce certain types of spidering. Any thoughts?


  • Portyankina by Portyankina scientist


    We have thought that some layers of SPLD are composed of a material that supports erosion just enough so that spiders form in there but do not get erased too fast. This was our explanation on why not all layers show spiders. I am unaware of any special types of spiders associated with either crater floors or SPLD, if you can show us some examples of what you saw, it would be really interesting.



  • Kitharode by Kitharode moderator

    Many thanks Anya. I'll try to gather some images to show what I'm thinking. I admit, I've only got one spider in a crater so far. 😃

    Something else you might help me with: I'm looking at images from around 'Inca City', but not the city itself, and I'm seeing lots of layers. At least they look like layers to me. Images like this:

    Now, I've always worked with the idea that the Inca City region as a whole was well outside the SPLD because I use this map:

    But now I'm thinking that the map doesn't really show the full extent of the layers and that the outer reaches go far beyond the map. Alternatively the layers I see are indeed layers, but they're different to the SPLD. Or, of course, they might not be layers. What say you?


  • p.titchin by p.titchin

    Hi Kith, I've been puzzling over these amazing layers all year. As you say, they don't fit in the PLD area.I think I read somewhere that this 'western', (far eastern) area, as well as having many small chasmae with outflow deposits, has an extensive area of 'proglacial' deposits extending well beyond the current polar cap. Could these be featuring? I shall follow the thread in hope of answers, (and probably many more questions!) :-p


  • Kitharode by Kitharode moderator in response to p.titchin's comment.

    Yes, there are some fairly significant differences I think between the 'western' side of the pole (the Inca City side) and the eastern side (Manhattan, etc). The SPLD's, now I think about it, could well go beyond the map we have because it might only be able to show, say, 0.5km altitude and above. The layers I see around Inca City might well be SPLD, just not very thick.

    I'm not absolutely sure what I'm asking, or trying to find out, or what I should be looking for - you know what gut feelings are like - but it's something to do with these differences on either side of the pole. It's also to do with these 'other layers' that I need to illustrate. My gut feeling is saying that 'this layering does/does not support 'this' type of spider', or 'spiders like this are found in this type of layer'. There's the ghost of an idea about 'recent layers' (non SPLD) forming spiders in non-spider areas. All very vague, but I'm having fun.

    To put my hunch another way; I've seen masses of large branching dendritic spiders on the 'east-side', but I'm struggling to find any on the 'west-side'. One obvious reason for this is that I haven't looked at all the images yet. Still ... 😉


  • Kitharode by Kitharode moderator

    PS: Large dendritics can be found 'west-side', in the zones of Inca City, but I'm thinking that's because the enclosed floors of the zones have a layer of stuff on them; a non-SPLD layer, a dust dripping off the walls layer, or something. Dendritics can be seen there, but I don't see them anywhere else in the surrounding landscape. The stuff that collects in craters, or in secluded alcoves, also seems to have collected as a 'layer'. These seem (gut-feeling) to be areas where spiders exist in an otherwise spiderless environment.

    Like I said, all very vague.