Figure 8 from Richard K. Bambach, Andrew M. Bush, Douglas H. Erwin (2007) "Autecology and The Filling of Ecospace: Key Metazoan Radiations" Palaeontology 50(1):1–22. "Change through time in realized ecospace. Top line represents all recorded modes of life, middle line represents modes of life of skeletal fauna only; bottom line records mean number of modes of life for single assemblages. For the Recent, the open circle represents those recent taxa with readily preserved hard parts, and the open circle containing an asterisk represents those taxa with a diverse fossil record."