[Glorantha] Spider Woods - why no record in the First Age?

[Labrygon at aol.com]

I've got an obscure question for the list concerning the intelligent spiders 
living in Dorastor (Dorastor: Land of Doom p23). Why are there no records of 
the Spider Woods from the First age? Did no  one notice them? Have they only 
appeared since Dorastors reawakening - although they have memories of the Gbaji 
wars so that cannot be true?  

Any ideas why it specifically mentions that there is no record from the first 
age?

Keith