To study the LDG, scientists have collected lots of data. Click on the button below to see these data. Each of these graphs shows some evidence relevant to the question of whether or not the LDG is real.
Notice that some of the graphs seem to be missing half their data. What does this mean? That there are no snakes, frogs, lizards, termites, or ocean fish in the Southern hemisphere? Of course not. It just means that we don’t yet have information about how many of these species are found at different latitudes in the Southern hemisphere.
This is not unusual. Scientists never have all the evidence relevant to a particular idea. Part of their job is to identify patterns and figure out explanations based on the available evidence — and to collect new evidence when it is needed to answer questions.
- Based on the evidence presented above, do you think that the LDG is real — in other words, are more species generally found at lower latitudes than at high ones? Explain how the data above support your thinking.
- What sort of evidence would it take for you to change your mind about this?