Relative dating of fossils activity
Wolfe showed that, in general, the shape of the leaf margin, or edge (Fig. The higher the proportion of plants with smooth (‘entire’) margins, the higher the temperature of the environment; leaves with toothed edges by contrast, tend to dominate in cooler climates.
Wolfe went on to compare many combinations of leaf CLAMP is a very useful tool for researchers trying to identify palaeoenvironmental signals in fossil leaf assemblages.
Thus, toothed margins apparently help plants in temperate regions to maximize their growth and productivity at the start of the growing season.
Temperate floras contain the highest proportion of leaves with toothed margins, and this proportion decreases with increasing temperature.
Studying them can help us to reconstruct the anatomy, behaviour and evolution of long-extinct organisms.
Perhaps less obviously, fossils are also among the most important sources of information for scientists attempting to learn about past (palaeo) climates and environments — a major focus of research in Earth and environmental sciences, motivated in part by concerns over future climate change. 1), in particular, can be useful for decoding past climate signals.
It also has difficulty with some types of climate or vegetation, such as rainforests.
A simpler method is leaf-margin analysis, which makes use of the observed relationship between the shape of the leaf margin (entire versus toothed) and the climate to estimate palaeotemperatures from fossil leaf floras.