Terrestrial Palaeoecology and Global Change

270 Valentin A. Krassilov. Terrestrial Palaeoecology
(cyanophytes) in their symbiotic roles and habits. Both phylogenetic analysis and palaeontological
evidence indicate great antiquity of lichens that gave rise to various nonlichenized
groups of fungi (Lutzoni et al., 2001).
Fungi emerged as dominant herbivores and detritivores long before animals (see Taylor,
1990 on various forms of plant – fungi interaction in the Devonian). In symbiotic systems,
fungi facilitate plant propagation as animals do. The Devonian fungi developed a tree habit
(Prototaxites: Hueber, 2001) in parallel to, or even in advance of, the higher plants.
Soil appeared long before the higher plants. Traces of pedogenesis go back to the
Precambrian (Retallack, 1986a; Retallack et al., 1984). The Ordovician palaeosols lack
plant roots but contain mycelial tubes as well as deep burrows (Retallack, 1985a; Feakes
& Retallack, 1988) suggesting their origin as the fungal–arthropod systems. The Late
Silurian records of diverse littoral communities of higher algae and algae-like plants (Fig.
107), with probable ancestral forms of higher plants among them, suggest that air-borne
a
b
Fig. 107. Before the conquest of land:
A littoral assemblage from the Late
Silurian of Podolie, Ukraine; (a) a
limestone quarry near the Kudrintsy
Village; the girl stands on a dark organicrich
layer with algal and conodont
remains, (b) slab covered with Caulerpatype
fronds resembling an early land
plant Baragwanathia, (c) cleared frond
showing a filamentous structure, (d) a
verticillate-type frond from the same
assemblage.
c
d