Scientific American is the essential guide to the most awe-inspiring advances in science and technology, explaining how they change our understanding of ... How closely related … A clade (or monophyletic group) is a group of species that includes an ancestral species and all of its descendants (i.e. The other species of ape and Man are very closely related. b. can interbreed, but not produce fertile offspring. And if two species are related closely enough (as with, for instance, donkeys and horses), they might be able to produce hybrid offspring. They said something was wrong, but then they accepted it,” Pinheiro says. longer two creatures’ developing embryos remain similar, the more closely related they are. Analogous structures are not necessarily evidence that two species came from a common ancestor. c. Creatures have vestigial structures or remnants of structures that were used for one function in an ancestor, but are no longer used for that function. ... How can you know if two species are closely related? They are closely related have more similar DNA. Although the two species are not at all closely related, they may appear quite similar as a result of Species X and Y share a greater number of homologies with each other than either does with species Z. Start studying Biology chapter 18. true T/F: The ribosomal RNA (rRNA) genes of different organisms are often compared as a means to classify them because rRNA genes evolve much more slowly than other genes. Technically, Man is a species of ape. The more recent the ancestral population two species have in common, the more closely are they related. c. are reproductively isolated from each other. T/F: Two organisms present in the same genus are usually more closely related to each other than to organisms in other genera. U, V, W, and Z. when cross-population is attempted between two closely related, sympatric species of violets (species A and B), it is found that the pollen (which contains the male gamete) of species A cannot reach the egg of species B because it lacks the proper enzyme to travel down to the location of the egg. By checking their DNA sequences. It is more likely they came from two separate branches of the phylogenetic tree and may not be closely related … The prevailing view is that different species do not interbreed naturally and that any hybrids that do form, are sterile. homologous: The following data table summarizes the number of differences in amino acid sequences found for four different species. Structures such as these are said to be _____. e. can interbreed and produce fertile offspring. Two plant species live in the same biome but on different continents. species B and species C: The structure of a certain blood protein was compared among four organisms. Two organisms present in the same genus are usually more closely related to each other than to organisms in other genera. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Previous studies suggested that past hybridization had resulted in all polar bears having genes that came from brown bears. <