For a larger picture click the thumbnails.
 
1. Two views of geological time



The sequence in which organisms first make their appearance is assumed to be an evolutionary one because it is interpreted as taking place over billions of years. The timescale determines the way the sequence is interpreted. As summarised by these two diagrams, the sequence itself, however, looks much more like one of pre-existing life gradually recovering from a global catastrophe and gives grounds for the timescale to be questioned.

2. The sequence of rocks in time

The earth’s rocks can be analysed into successive time zones, from the Quaternary down to the Archaean. The lowest division, the Hadean, is not represented by whole rocks on Earth, though there is strong indirect evidence that rocks and oceans existed then (see Water, water everywhere). According to recolonisation theory, a cataclysm at the end of the Hadean consigned the pre-Archaean world to the Earth’s depths. Also shown are a few representatives of major animal groups at the point where they first appear. The diagram is not to scale in relation either to time or to stratigraphic thickness.
 
 
 
 
3. Representations of absolute time

This diagram shows the same divisions in proportion to the time attributed to them. Left is the radioisotope-based timescale, whereby almost all evolution was concentrated in the final sixth of life’s history. The compression appears particularly drastic in the Cenozoic, the divisions of which are too small to show separately and are therefore summarised as ‘Palaeogene’ (from the Palaeocene to the Oligocene) and ‘Neogene’ (from the Miocene to the present). Right is the same sequence recalibrated on the basis that radioactivity was much higher in the past and progressively declined. The timescale is anchored to empirically derived values for the terminal Hadean/earliest Archaean, part of the Silurian and part of the Cretaceous, but otherwise remains tentative and approximate. Note that Cenozoic mammals appear much earlier in the sequence and the Precambrian is proportionally miniscule, though still a significant length of time in real terms.

4. Detailed stratigraphic chart

The chart is taken from The International Commission on Stratigraphy (ICS) and gives some idea of how finely it is possible to subdivide geological time.

5. Overview of the fossil record

This image is a schematic representation of the first appearance and subsequent diversity of major groups of organisms in the fossil record. They show no evidence of being linked together in a single ‘tree of life’.

6. Diversity over time

Graphs showing how the number of marine and terrestrial families has increased over time. The patterns are consistent with both evolution and recolonisation theory, but not with the idea that a Flood took place in the Palaeozoic and Mesozoic (which would predict a pattern of sharply decreasing diversity). Source: M. J. Benton, Diversification and extinction in the history of life, Science 268:52-58 (1995).

7. The insect explosion

Chart showing a summary of the fossil record of insect orders, where spindle thickness corresponds to number of families at any one time. The membership of some orders is uncertain (e.g. ants may not be related to bees/wasps) but in general they are probably equivalent to the created ‘kinds’ – their fossil record indicating an amazing pre-programmed capacity for variation. Of the 41 orders shown, 17 suddenly appear in the Carboniferous and a further 12 in the Permian. Estimates of the number of current insect species range from 5 million to 80 million. (C.C. Labandeira & G.J. Eble, Gondwana Alive: Biodiversity and the Evolving Biosphere (2005))

8. The mammal explosion

George Gaylord Simpson, one of the founders of Neo-Darwinism, said this about the thirty-two orders of mammals:

The earliest and most primitive known members of every order already have the basic ordinal characters, and in no case is an approximately continuous sequence from one order to another known. In most cases the break is so sharp and the gap so large that the origin of the order is speculative and much disputed… This regular absence of transitional forms is not confined to mammals, but is an almost universal phenomenon, as has long been noted by paleontologists.

Tempo and Mode in Evolution (1944), pp 105, 107

The image here is a redrawn version of figure 316 in A. S. Romer, Vertebrate Paleontology (1966). Most of the mammal orders appear in the Eocene, the third time division from the bottom. Again, they are not necessarily equivalent to the created kinds. For example, the order Carnivora is likely to include several non-related groups.

9. Climate cycles as reflected in sedimentary strata

Alternating limestones and clays in the geological record usually reflect changes in climate. On the basis that the Earth is billions of years old, geologists attribute them to astronomical cycles that take 20,000 years or more to complete (known as ‘Milankovitch cycles’). However, the direct sedimentary evidence suggests that the cycle we should be thinking of is the annual alternation of summer and winter.

The diagram shows the regular alternations of limestone and limey shale in the Greenhorn Formation, Colorado. The limestone derived mostly from marine plankton, the shale from terrestrial uplands, which were more intensely eroded during the winter, owing to heavier rains. The cycles are approximately 1 metre thick, with burrowing increasing from bottom to top. Burrowing organisms can colonise a new surface in a few weeks, and can destroy all traces of bedding in a few months or years, yet strata that are only partially burrowed are common in the geological record.

For an in-depth discussion of these issues, see How old is the Earth?

10. The effects of higher ‘c’

The standard geological timescale obtains its dates by radioisotope dating, but what if the underlying assumption of constant half-lives was invalid? It is certainly possible. The rate at which a radioactive element decays depends on the speed of light, so if the speed was faster in the past, the rate of radioactive decay would also have been faster. The diagram shows just how critical the assumption of constant decay is. With higher ‘c’, radioisotope clocks tick faster, the processes that the clocks measure are faster, and the rates at which stars go through their cycles are faster. The chronology of the entire universe is affected.