AFAIK Science has yet to provide a good description or even a good evolutionary reason for consciousness, in that it disappears when we sleep and is nearly instantly re-manufactured complete with an intact and coherent personality, a binding thread, if you will, upon awaking. Please don't get me wrong I am not seeing this as any kind of failure on the part of Science but rather some shared by the provincial conceit of being human ("What a piece of work is man, how noble in reason, how infinite in faculties, in form and moving- how express and admirable, in action - how like an angel, in apprehension how like a god!" - Hamlet via Willy) and lack of the appropriate technology. It disturbs me some how we write off so-called lower creatures, especially Porpoises and Whales, as possessing only instinct when they can have more neural connections per volume, more brain mass, etc etc. It pleases me somehow that our very description of Life has had to be altered by so-called "extremophiles".
In any case, regarding spiders weaving webs, I wonder how our definition of instinct applies when the manner in which they build webs can be so similarly affected by administering psychoactive drugs. Here are some informative links and one really fun interactive video.
Spiders On Drugs
Effects Of Drugs And Alcohol On Spider Webs • VideoSift: Online Video *Quality Control
Spiders On Drugs
It pleases me most that imaginative scientists have begun to actively imagine how other lifeforms may exist even among the higher clouds of Jupiter, or in the methane seas of Titan. I sincerely hope that life is discovered on Mars soon, and especially if it is not DNA based (or even carbon based) that 1) we recognize it as life, and 2) we get the implication that Life is essentially ubiquitous, something that chemistry just tends to do over a sufficient length of time.