| The
first fossils of multicellular green algae appear in the Cambrian
strata of the early Paleozoic Era. Yuknessia as shown here was a
thin, frond-like green, carbonaceous algae resembling modern kelp.
Complete algal fossils, identified as Yuknessia simplex and Margaretia
dorus as seen here have also been found in the Burgess
shale of Canada; both genus have been classified as Chlorophytes,
a distinct branch of green algae from the Streptophytes that eventually
gave rise to the land plants. This taxon has not been well studied.
Together
with filamentous cyanobacteria (commonly called blue-green algae),
algae like Yuknessia built large reef systems that not only supported
Cambrian marine life, but photosynthetically augmented atmospheric
oxygen levels thus further driving the amazing eukaryotic diversification
known as the Cambrian
Explosion.
This
is as particularly well preserved a specimen.
Reference:
The Fossils of the Burgess Shale by D. E. Briggs, et al.
Also
see: Utah Cambrian Explosion
Fossils
|