Biology Reference
In-Depth Information
Leonardo considered the interpretations of fossils prevalent during his
time as ludicrous—“such an opinion cannot exist in a brain of much reason.”
His opinion that fossils were “remains” of past life has been modifi ed to “evi-
dence” of past life in recognition that shell, bone, or organic material need
not be present to document life, but may include indirect evidence such as
worm borings, amber (fossil plant resin), phytoliths (plant crystals), bioge-
netic sediments, biochemical fossils, and birefringent compounds. Once this
view was generally accepted, augmented by the principles of stratigraphy
and increasingly accurate estimates of the age of the Earth, the study of fos-
sils began making meaningful contributions to our knowledge of evolution,
lineages, environments, and ecosystems. They provided what the poet Ed-
ward FitzGerald in 1847 called our “vision of time” (Terhune and Terhune
1980). Even so, there was a transition period through the 1800s when both
biblical literalists and “Old Earth” geologists grappled with the meaning of
a fossil record far less complete and more poorly understood than today.
Part of the subsequent polarization in views came from the growing belief,
as Edward Forbes realized as early as 1851, that scientists must present the
results of their research “in plain, readable, and comprehensive language
. . . for if they do not do so, others, unqualifi ed for the task will impose a
sham philosophy.” Nearly a century later, John Crosse agreed, arguing that
“if men competent to the task disdain to popularize science, the task will be
attempted by men who are incompetent, but popularized it will be” (both
Forbes and Crosse quoted in O'Conner 2007, 213-14).
PALEOBOTANY
The study of plant fossils is traditionally designated as paleobotany if
it deals primarily with macrofossils (Stewart and Rothwell 1993; Taylor
et al. 2009), and palynology (from Greek palÐ , fi ne fl our or dust) if it deals
with modern and fossil spores, pollen, and other plant microfossils (Tra-
verse 2007). In those parts of the geologic column where organisms or
their relatives, at least to the level of families, are often still represented in
the modern biota (roughly Middle/Late Cretaceous to Recent), the basis for
both approaches is comparative material obtained from fi eld or herbarium
collections (fi g. 4.2). The latter include plant specimens mounted on her-
barium sheets with label data giving the name of the plant, collector and
collection number, place (via GIS systems), and ecology, that is, vegetation
type, habitat, and altitude (fi g. 4.3). As noted previously, this information
is currently being databased, together with relevant literature, images, and
maps showing global distributions. Collections in the major herbaria are
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