Plate 1. The 2009 geologic timescale accepted by the International Commission on Stratigraphy. The timescale shows eras, periods, epochs, and ages for the Phanerozoic eon and eons, eras, and periods for the Precambrian supereon. The age in millions of years of each time interval is shown at the left. Note that the height of each time interval is scaled linearly in time, but that the Cenozoic, Mesozoic, Paleozoic, and Precambrian columns each have a different linear scale.

Plate 2. Saddle-shaped correlational selection in garter snakes favors specific combinations of escape behavior and color patterns. The surface shown is estimated from a three-year study of survival of more than 600 individual snakes in the wild. Individuals with striped patterns were most likely to survive if they performed few reversals, and those with more spotted patterns survived if they performed many reversals. The other combinations of color pattern and behavior experienced high mortality.

Plate 3. An example of the rapid generation of a chimeric gene: the Jingwei gene in Drosophila. Based on the distribution of Jingwei in related species, the lineage of this gene was inferred in the phylogeny of three species, D. yakuba and D. teissieri, and D. melanogaster. Sequence analyses of genomic DNAs and transcripts reconstructed the process of gene evolution, revealing that retroposition, DNA-based gene duplication, and exon/domain shuffling worked together to create the Jingwei gene 3 million years ago in the common ancestor of the African Drosophila.

Plate 4. Aptamer selection experiment. (Illustration prepared by Angel Syrett.)

Plate 5. Phage display experiment. (Illustration prepared by Angel Syrett.)

Plate 6. Multiplex Automated Genome Engineering (MAGE). (Illustration prepared by Angel Syrett.)

Plate 7. Digital evolution in the Avida-ED system begins with a digital organism with a circular genome consisting of a sequence of instructions that cause its behaviors, including (A) self-replication. Random mutations in the genome of the daughter cell as it buds off from a parent cell can result in new variations that may be neutral, advantageous, deleterious, or lethal. The genome of a descendant cell (B) may thus be significantly different from its ancestors. Natural selection occurs in a population of digital organisms (C) as they compete in a virtual environment that differentially rewards possible traits. (http://avida-ed.msu.edu.)