On what basis do you calculate Mars age, the age when the magnetosphere was active and the age of the spiders? Perhaps your timelines are incorrect. Please be more specific when offering critiques. I enjoy a good challenge, but not with unfounded "facts" thrown out without support. Dogma/religion is bad. Information is good. Source of information is better.

If you're basing your "age" calculations off cratering and channeling formation, there is a good possibility that the "dating theories" are flawed. If many of the features were carved by electrical machining during an electrically active phase, and not by longer term "erosion" or "ballistic cratering" the traditional estimates of age may be completely skewed (as it is, they're only theoretical anyway; the fact that people simply quote the "age" as fact makes me sick to my scientific stomach). As it happens, cratering can be created in the lab via electrical discharges. Electromagnetic phenomena can be scaled over many orders of magnitude. Sufficiently to create planetary cratering and "channels." And these can be carved over a very SHORT time frame. Seconds, minutes, hours, days, years, rather than the eons predicted by "impact" and "erosion." The fact of the matter is we still see electrical processes happening on Mars.

Ever heard of the miles high dust devils of Mars? Interesting that they're electrically charged... Interesting also that Mars' atmosphere should be FAR too rarified for Dust Devils to form via convective currents, especially on the MASSIVE scale they form on Mars. More like formed via ELECTRIC currents. But some are simply too set in their ways to see it. It's okay, it'll all come out eventually. ;o]

Ohh, and in case your a proponent of the dust as "cause" theory of dust devil formation, think again.

http://www.nasa.gov/vision/universe/solarsystem/2005_dust_devil.html

Effect has been mistaken for cause. Terrestrial dust devils have been observed for significant timeframes without any visible dust ejecta from the surface by Project MATADOR. Dust devils were observed by LIDAR and for a "significant portion of their lifetimes they were FREE OF DUST." But still fully formed and detectable. Hmm, but they still have their electrical features... So, electrical filaments without dust spinning around them. What does it all MEAN? Dust devils are a charge sheath vortex that machines dust as an effect. The dust in itself is NOT a cause, nor is it required in order to sustain a dust devil. Nope, dust devils are powered by something far greater. Electricity.

From the Nasa article:

The team believes they made the first Doppler LIDAR measurements of an invisible dust devil. "Some researchers think a dust devil may need dust to sustain itself, but here we recorded a very large one that was essentially free of dust for a substantial part of its lifetime," said Dr. Brent Bos of NASA's Goddard Space Flight Center in Greenbelt, Md.

And we've seen Dust devils on Mars leaving mile long blackened tracks on the surface of the planet. So, we can say with a fair degree of certainty that Mars is still electrically active. Ohh, certainly, not as much as it used to be. It's calmed down a lot in recent history (I'd say in the last 3-6 thousand years, give or take a millenium). But once upon a time, it was a highly charged body with a LOT of electrical activity. The scars of it are everywhere. The dual arcs of Valles Marineris, Mamers Vallis (tell me that doesn't look electrical with a straight face), the "spiders." The evidence is there, staring us in the face. We simply need to see it for what it is.

Time for you to go back to the drawing board. ;o] Have a good one.