To the origins of the animal kingdom  More advanced analyses,
but not without flaws  Even if phylogenomics has allowed a leap
forward in the understanding of the evolutionary relationships
between species, it is not a panacea. ‘This approach also has
disadvantages. It is not enough to increase the number of genes
to be compared to obtain a reliable tree,’ explains Denis
Baurain. ‘You still need to use carefully checked data and
sophisticated analysis methods,’ insists the researcher. It is
precisely that which Denis Baurain, working together with a
Canadian team at the University of Montreal, underlines in an
article published in PLoS Biology (1). What did the common
ancestor of all animals in existence look like? That is, before
the Cambrian explosion over the course of which the major
current branches sprang to light. It is to this question that
three concurrent phylogenomic studies have tried to answer (2,
3, and 4). ‘And yet the latter came to three different
conclusions, only one of which is correct,’ (F