Why are phylogenetic trees hypotheses?

1 Answer
Nov 20, 2016

We're not time travellers.


Because we can't actually witness the evolution of species over time, we only have a certain body of evidence for the interrelatedness of certain species. We can't be 100% sure about any evolutionary relationship, due to our inability to travel to the past and observe long periods of time in which speciation occurs, nor can we ever be 100% sure about the validity of that body of data we have that suggests evolutionary relationships.