Gce Model Questions Vol1 2023 Biology Question 37

Fossil evidence provides the following data for a lineage of extinct mammals:\n\n- Species A (appearing at \(150\) Ma) had an average fore‑limb length of \(30\) cm.\n- Species B (appearing at \(120\) Ma) had an average fore‑limb length of \(45\) cm.\n- Species C (appearing at \(90\) Ma) had an average fore‑limb length of \(60\) cm.\n\nAssuming limb length evolved linearly with time between Species A and Species C:\n\na) Calculate the rate of change in fore‑limb length in cm per million years.\nb) Using this rate, predict the expected fore‑limb length of a specimen that would have lived at \(105\) Ma.\nc) Compare the predicted length with the observed length of Species B and state whether Species B supports the linear model.