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Each species lives about 1 million years, with a large range of variance: The pearl boat,

an octopus, for example, has survived effortlessly through the last half billion years,

including global mass extinctions in the Permian and Cretaceous, as has the cockroach.

With eukaryotes, there was also the possibility of investing in complexity. After all,

these higher cells with nuclei are able to store about a hundred to a thousand times more

genetic information than bacteria. This allows much more material for evolution. Splicing

can also combine one and the same gene into numerous different proteins. And sexual

reproduction also allows something new to be tried out in a diploid chromosome set in one

allele of a gene (i.e. the variant from the father or the mother), since initially the already

fairly optimal original variant of the gene in the other parent also pre-exists in the cell. This

led to more and more complex organisms, and these also showed more and more complex

behaviour. Until the appearance of humans, insects dominated on land among the higher

organisms (eukaryotes) and among these the state-forming ants. With the appearance of

humans, the total biomass of insects is still greater among higher organisms, but our civi­

lization (including buildings and industry) has now become the dominant species on the

planet for the ecological footprint and thus also at least for the necessary consumption of

biomass (since 1950, is referred to by geologists as the “Anthropocene”, new age). Before

that, however, mammals gradually evolved higher since the Jurassic (200–140 million

years before our era) and, with the extinction of the dinosaurs 65 million years ago, clearly

outranked their present-day descendants, the birds, in occupying the ecological niches.

But insects were still the dominant species. However, hymenoptera (bees, ants, wasps)

only developed massively with the appearance of flowering plants, also in the Tertiary

period (from about 65 million years ago).

The brief overview shows: It is not easy to interpret evolution correctly, and one also

needs detailed data on the Earth’s ages and the predominant species as well as the geologi­

cal and climatic conditions. This book cannot do that. We will next look in more detail at

how phylogeny (family tree science) can be used to infer the evolution of different species

based on shared or unshared characteristics via calculated ancestors. The most accurate

phylogenetic trees require a lot of practice and systematic comparison of all available

information (e.g. alternative phylogenetic trees).

One should also know the species exactly in their macroscopic characteristics. It is also

important to look at several molecular sequences, which are used for a phylogenetic tree,

especially since proteins tolerate mutations at different rates. “Molecular clocks” go at

different rates: Histone proteins hardly change at all because they are central and interact

with many proteins. In contrast, less important proteins, or those that interact with few

other proteins, can change much faster. Marker proteins can provide clarity here: fre­

quently described molecules that occur in very many species, such as ribosomal RNA or,

in the case of proteins, pyruvate kinase.

Phylogeny and other data from paleontology and molecular biology thus show, for

example, how cytochromes (also important marker proteins) have evolved in comparison

to hemoglobins. Such studies are supported by protein structure analysis. Interestingly,

embryology can also often help: In order to form a new structure (for example, when a

10  Understand Evolution Better Applying the Computer