Why are parts of the fossil record missing?

The fossil record, however, is quite incomplete. Here’s one major reason why: Sediment has to cover an organism’s remains in order for the long fossilization process to begin. Most organisms decompose before this can happen. Plus, fossils may be set in stone, but they’re far from impervious.

Are insect fossils common?

Fossil insects are more common than is generally supposed, especially their disarticulated remains, despite lacking a mineralized skeleton. Some of the best preserved insects occur in amber and in ancient lake deposits, both relatively low energy environments, from the Late Triassic onwards.

Why are there so many insect species perspectives from fossils and phylogenies?

There is evidence that the species richness of insects has been enhanced by: (i) their relative age, giving time for diversification to take place; (ii) low extinction rates. There is little evidence that rates of origination have generally been high or that there are limits on numbers of species.

Are insects ever fossilized?

Many insect types, traces of which have not yet been discovered, must have been produced during the explosive periods of evolution in Carboniferous and Permian times. The Orthoptera (grasshoppers) and the Plecoptera (stoneflies) have been found as fossils even in late Carboniferous times.

How are insect fossils formed?

Fossils can form in unusual ways. Small bugs or insects can become trapped in tree sap. Eventually the sap hardens and forms the semiprecious material called amber. In order to become fossilized, animals must die in a watery environment and become buried in the mud and silt.

What is insect fossil?

Insects have been preserved as fossils in concretions, amber, shales, and the LaBrea tar pits. The oldest fossil insect dates back to the Upper Carboniferous period. However, six-legged arthropods, such as the springtails (Collembola), have been found in Devonian rocks (Wooton, 1981).

Why is there so many species of insects?

There is evidence that the species richness of insects has been enhanced by: (i) their relative age, giving time for diversification to take place; (ii) low extinction rates. Comparative studies indicate that phytophagy generally increases net diversification rates, and reduces extinction risk.

What caused the diversification of insects?

The most common hypotheses propose that insect diversity either results from: (i) low extinction rates and resilience to mass extinctions; (ii) the acquisition of key innovations that allowed them to radiate into newly formed niches, or (iii) the appearance of new niches that favoured the diversification of some clades …

How are insects fossilized?

Insects have been preserved as fossils in concretions, amber, shales, and the LaBrea tar pits. The oldest fossil insect dates back to the Upper Carboniferous period.

Why is the fossil records incomplete?

There are gaps in the fossil record because many early forms of life were soft-bodied. The soft parts of organisms do not form fossils well. This means there is little information about what these organisms looked like. Any traces of fossils that there may have been were likely destroyed by geological activity.