Answers could include one of the following:

Oxygen transporting proteins

• Biochemical evidence supporting evolutionary relationships can be found in the similarities of oxygen-transporting proteins across species.
• Haemoglobin, the primary oxygen-carrying protein in vertebrates, shows structural similarities across diverse animal groups, indicating a common ancestral origin.
• This evidence supports Darwin and Wallace’s theory by demonstrating common descent with modification. 

DNA

• One type of biochemical evidence supporting evolutionary relationships is the similarity in DNA sequences and proteins across different species.
• The more closely related species are, the more similar their DNA and protein sequences tend to be, indicating common ancestry.
• In Australian marsupials, DNA analysis has revealed close genetic relationships between seemingly diverse species like the Tasmanian devil and the numbat.
• By supporting their common evolutionary origin, DNA provides support for Darwin and Wallace’s Theory.