Evolution CAQ

🐝 Evolution Created Tags Explain how the relationship between the morphological structures provide evidence to support the theory of evolution Organisms with anatomical homology have morphological structure such as bones that they inherited from a Common ancestor Refer to examples in the question/ the pentadactyl 125 limb structure in forelimb of organisms are homologous structures have different functions but highly similar in structure with those of a common ancestor, showing descent with modification as the ancestral structure was altered by natural selection in the different organisms to suit their specialised emvironments, resulting in variations of the ancestral structure showing that divergent evolution has occured Advantages of molecular methods in classifying organisms Molecular data such as nucleotide and amino acid sequences are quantifiable, in abundance and open to statistical analysis amd easily converted to numerical form. The degree of relatedness between different species can be inferred and quantified by calculating nucleotide differences between species (advantages in constructing phylogeny) Molecular data can be easily described in an unambiguous manner as A, C, G and T is easily recognisable and cannot be confused. Protein and nucleic acid sequence data are precise and accurate. This facilitates the objective assessment of evolutionary relationships. Molecular data is based strictly on heritable material. August 6 , 2025 910 AM Ev olution 1

All organisms can be compared with the use of some molecular data as all living organisms have nucleic acids and proteins, so molecular data can be collected from any organism. DNA information provides abundance of data for analysis and it allows easy homology assessment. Mitochondrial DNA does not undergo recombination thus any changes to DNA is due solely to the accumulation of mutations over time making it the ideal candidate for a molecular clock as we can estimate the time of speciation DNA sequence data can be used to compare species which are morphological indistinguishable due to convergent evolution or are because they are very closely related As changes in nucleotide sequences accumulate over time with clockwork regulation, we can estimate the time of speciation of modern to ancient species and place the speciation events on a timescale above differences between classification and phylogeny Classification Phylogeny Groups organism based on overall morphological similarities and does not take into account the evolutionary history of organisms Trace evolutionary history of organisms based on ancestor-descendent relationships Group organisms into a kingdom, phylum, class, order, family genus and species using a hierarchical classification Arranged based on their evolutionary relationship with each other with each organism assigned a position on a branching tree relative to other organisms Organism is presented as a binomial nomenclature/name Or