Evolution: evidence of change

[Ayeshaa]

Hey I have a few questions on this topic, and would appreciate if you could help add to my simple answers =) Thanks in advance.

How is adaptation related to fitness?

^Its related to fitness because adaptation enables organisms to become better suited to their environment and fitness is the physical traits and behaviours to enable organisms to survive and reproduce.

How might relative dating provide innacurate data?

^ Relative dating might provide innacurate data because scientists cant determine how long it took for the layers to form, so they wouldnt be able to determine the actual age of the fossils, the depth of the layers can vary each year, and natural causes, such as erosion or earthquakes change the layers of sediment.

what are some problems faced by paleontologists when reconstructing the history of life on earth?

^ the fossil record is incomplete, the quality of the fossil, and you cant always find all fossils.

how does biochemistry support the idea that all living things evolved from common ancestors?

^is it because of dna/rna genes being evolved and transferred to the young?

[Luxorien]

(Standard Disclaimer: Your instructor is likely looking for specific answers, so the best place to look would be your notes/handouts/textbook.)

Without context, my advice would be:

• Take another look at your definitions for adaptation and fitness. You're on the right track, but I would differentiate between them more clearly. Fitness is a measurement and an adaptation is something that an organism has.
• Biochemical evidence of common ancestry has to do with the similarity of the molecular machines in different organisms. For instance, protein sequences can be used to construct phylogenetic trees, and many biochemical structures, like flagella and ion channels, are remarkably similar in different organisms. Of course, my favorite biochemical example of common ancestry is the stereochemistry of amino acids. With a few weird exceptions, all living things use L-amino acids. D-amino acids would work just as well, but our common ancestor happened to use L-aminos, so that's what we use.

[Ayeshaa]

Thanks so much for the help and for replying