I’m trying to run an ancestral character estimation assuming equal rates using the “ape” package. I’ve read my phylogeny in as a NEXUS file and my discrete traits in a list.

However, when I try to carry out the “ace” command, I get the following error:

> equalrates_model = lapply (var.list, function (x) ace (x, tree,
+                                                        type = "discrete",
+                                                        model = "ER"))
Error in names(obj$ace) <- phy$node.label : 
  attempt to set an attribute on NULL

Here is the structure of my tree:

> str (tree)
List of 6
 $ edge       : int [1:92, 1:2] 48 49 50 51 51 50 52 52 53 53 ...
 $ edge.length: num [1:92] 0.0137 0.0146 0.0271 0.0389 0.0674 ...
 $ Nnode      : int 46
 $ node.label : int [1:46] 1 2 3 4 5 6 7 8 9 10 ...
 $ root.edge  : num 0
 $ tip.label  : chr [1:47] "Ectemnius_sonorensis" "Dasyproctus_spec" "Lindenius_panzeri2" "Crossocerus_quadrimaculatus" ...
 - attr(*, "class")= chr "phylo"
 - attr(*, "order")= chr "cladewise"

and here is the structure of my list of traits:

> str(var.list)
List of 12
 $ Species    : Named chr [1:47] "Ectemnius_sonorensis" "Dasyproctus_spec" "Lindenius_panzeri2" "Crossocerus_quadrimaculatus" ...
  ..- attr(*, "names")= chr [1:47] "Ectemnius_sonorensis" "Dasyproctus_spec" "Lindenius_panzeri2" "Crossocerus_quadrimaculatus" ...
 $ Hemiptera  : Named int [1:47] 1 0 0 0 0 0 0 1 0 0 ...
  ..- attr(*, "names")= chr [1:47] "Ectemnius_sonorensis" "Dasyproctus_spec" "Lindenius_panzeri2" "Crossocerus_quadrimaculatus" ...
 $ Diptera    : Named int [1:47] 1 1 1 1 1 1 0 1 1 0 ...
  ..- attr(*, "names")= chr [1:47] "Ectemnius_sonorensis" "Dasyproctus_spec" "Lindenius_panzeri2" "Crossocerus_quadrimaculatus" ...
 $ Hymenoptera: Named int [1:47] 0 0 0 0 0 0 0 0 1 0 ...
  ..- attr(*, "names")= chr [1:47] "Ectemnius_sonorensis" "Dasyproctus_spec" "Lindenius_panzeri2" "Crossocerus_quadrimaculatus" ...
 $ Lepidoptera: Named int [1:47] 0 0 0 1 0 0 0 0 0 0 ...
  ..- attr(*, "names")= chr [1:47] "Ectemnius_sonorensis" "Dasyproctus_spec" "Lindenius_panzeri2" "Crossocerus_quadrimaculatus" ...
 $ Orthoptera : Named int [1:47] 0 0 0 0 0 0 0 0 0 0 ...
  ..- attr(*, "names")= chr [1:47] "Ectemnius_sonorensis" "Dasyproctus_spec" "Lindenius_panzeri2" "Crossocerus_quadrimaculatus" ...
 $ Coleoptera : Named int [1:47] 0 0 0 0 0 0 0 0 0 0 ...
  ..- attr(*, "names")= chr [1:47] "Ectemnius_sonorensis" "Dasyproctus_spec" "Lindenius_panzeri2" "Crossocerus_quadrimaculatus" ...
 $ Trichoptera: Named int [1:47] 0 0 0 1 0 0 0 0 0 0 ...
  ..- attr(*, "names")= chr [1:47] "Ectemnius_sonorensis" "Dasyproctus_spec" "Lindenius_panzeri2" "Crossocerus_quadrimaculatus" ...
 $ Araneae    : Named int [1:47] 0 0 0 0 0 0 0 0 0 1 ...
  ..- attr(*, "names")= chr [1:47] "Ectemnius_sonorensis" "Dasyproctus_spec" "Lindenius_panzeri2" "Crossocerus_quadrimaculatus" ...
 $ Psocodea   : Named int [1:47] 0 0 0 0 0 0 1 0 0 0 ...
  ..- attr(*, "names")= chr [1:47] "Ectemnius_sonorensis" "Dasyproctus_spec" "Lindenius_panzeri2" "Crossocerus_quadrimaculatus" ...
 $ Blattodea  : Named int [1:47] 0 0 0 0 0 0 0 0 0 0 ...
  ..- attr(*, "names")= chr [1:47] "Ectemnius_sonorensis" "Dasyproctus_spec" "Lindenius_panzeri2" "Crossocerus_quadrimaculatus" ...
 $ Mantodea   : Named int [1:47] 0 0 0 0 0 0 0 0 0 0 ...
  ..- attr(*, "names")= chr [1:47] "Ectemnius_sonorensis" "Dasyproctus_spec" "Lindenius_panzeri2" "Crossocerus_quadrimaculatus" ...

Any help in solving this error would be greatly appreciated.