The building blocks for such trees are the bone fragments that comprise the "fossil record". In the case of the hominids, the fossil record is growing all the time, causing much confusion and controversy. This arises from uncertainties about the age and/or the species identity of new finds.

The graphical representation of hominid evolution is anever-changing picture.

Try building a hominid family tree of your own using the "building blocks" you know about and the pointers provided here:

• the New Fossils;
• the New Confusions;

Test your understanding of hominid relationships by examing thephylogeny shown here, and:

• attaching aspecies name to each vertical bar marked with a letter (A - M);
• explaining the colour differences between vertical bars;
• explaining the question marks on the lines and bars;
• explaining the differences between black and blue lines in the phylogeny;
• listing all of the potential human ancestors discovered since 1999 that are not included in this phylogeny, and indicating their approximate ages.