Final answer:
Scientists determine relationships between fossil organisms and living organisms through comparative morphology, reconstructed DNA sequences from molecular fossils, and dating techniques. Advancements in technology allow for more accurate DNA analysis from fossils, providing greater insights into evolutionary history.
Step-by-step explanation:
While it's true that fossils rarely contain DNA due to degradation over time, scientists can still determine the relationships between fossil organisms and living organisms through several methods. One approach is to study the physical features of fossils and compare them with living forms to identify similarities and differences, suggesting common ancestry or the level of divergence through evolution. Moreover, molecular fossils, or preserved gene sequences, have been used to reconstruct probable DNA sequences of ancient species, helping to ascertain their relationships with modern species. Additionally, by dating and categorizing fossils, scientists can establish a timeline for when organisms lived, which helps in piecing together the evolutionary history.
Scientists use both relative dating and absolute dating to determine the age of fossils. The morphology of certain body structures, like the whale flipper which shares similarities with bird and mammal appendages, provides clues about a common ancestor. As technology advances, the analysis of DNA from fossil materials is improving, opening new possibilities for understanding the evolutionary relationships and adaptations of ancient plants and animals despite the skepticism and challenges such as degradation and contamination.
Finally, as genomic datasets increase, they provide a more comprehensive map of life’s evolutionary history, revealing surprising relationships such as the closer genetic ties between people and fungi than between fungi and plants. These strategies and advancements in technology are critical in unveiling the intricate web of life's history on our planet.