Final answer:
Early examples of molecular ecology include the preservation of oleanane in Permian sediments and the Miller-Urey experiments creating life's building blocks. Studies of colonial organisms like Volvox illuminate the transition to multicellularity. DNA analysis from fossils helps decode plant lineage evolution.
Step-by-step explanation:
Some very early, primitive examples of molecular ecology can be traced back to the use of analytical chemistry and molecular biology in studying fossils and the prebiotic Earth. The identification of oleanane in sediments from the Permian period, a compound previously found only in flowering plants, suggests that molecular structures have been preserved in environments free from oxygen, leading to re-dating the appearance of the first flowering plants. Furthermore, the Miller-Urey experiments successfully replicated the production of life's fundamental building blocks under simulated early Earth conditions, indicating how primitive biochemistries could have evolved into present-day metabolisms.
Colonial organisms like the algae Volvox are considered to be a bridge between single-celled life and multicellular organisms, showcasing an early evolutionary step. Lastly, shared cellular structures, nucleic acids, proteins, and metabolic chemistries signify a common ancestry with all life, dating back to the Last Universal Common Ancestor (LUCA). The study of fossilized nucleic acids, such as DNA and RNA, allows paleobotanists to understand evolutionary relationships and trace the molecular evolution of various plant lineages.