From Science News http://www.sciencenews.org/

Once thought to be the last remaining members of a plant lineage that went
extinct with the dinosaurs, modern-day cycads are now believed to have
diverged
from a more recent common ancestor.
Although cycad populations suffered major losses about 65 million years
ago when
dinosaurs — their once primary dispersal agents — went extinct, the plants
later
experienced a renaissance due to a global climate shift, a new study
suggests.
Living cycads diverged from an ancestral species that flourished around 12
million years ago, not from older dinosaur-era relatives, an international
team
of researchers reports online October 20 in Science.
To estimate the divergence time of living cycads, researchers used a
technique
called molecular clock analysis. First they measured the genetic
differences
separating 200 living cycad species. Since certain genetic changes
typically
accrue at a fixed rate once species radiate from a common ancestor,
scientists
were able to use this cycad DNA data, in conjunction with the fossil
record, to
predict a much more recent divergence. – Nick Bascom

My take -- one doesn't usually think of dinosaurs deftly plucking seeds
from a
cone to enjoy the fleshy aril; that's something a bird or small mammal
might
do. I wonder what the cycads were like that depended upon dinosaur
dispersal.

David E.
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