1978] 
Burnham — Social Insects in Fossil Record 
107 
A few species were described by Emery (1891) in Sicilian ambej, 
presumed to be Miocene, but these, like the specimens studied by 
Heer, are of questionable generic position. 7 
Another Miocene amber deposit has been found in Chiapas, 
Mexico, from which some one hundred ants have been recovered. 
Unfortunately, the majority of these are fragmentary, or otherwise 
too poor for determination. The assemblage does, however, suggest 
that the ant fauna in Mexico during the Miocene was essentially the 
same as might be found in that region today (Brown, 1973). 
Fujiyama (1970) described a single ant from the Chojabaru 
formation in Japan (middle Miocene) which he named Aphaeno- 
gaster axila, thought to be closely allied to the subgenus Dero- 
myrma. This is not particularly unusual inasmuch as Aphaenogaster 
is a world-wide genus, and several species are found in Japan today. 
Perhaps the most interesting of all Miocene material is an ant 
colony of Oecophylla leakeyi found in Kenya (Wilson and Taylor, 
1964). This is the first record of an actual, although fragmented, ant 
colony and contains a total of 366 specimens: 197 larvae, 105 worker 
pupae, and at least 64 workers. No Nearctic fossils of Oecophylla 
are known, but the species is well represented in European Tertiary 
deposits. Wilson and Taylor suggest on the basis of these fossil 
specimens that Oecophylla is a morphologically stable paleotropical 
genus which has persisted through most of the Tertiary with very 
little specialization. 
Apoidea 
The Apoidea form an interesting complex of social insects. Unlike 
the other social insect groups that are consistent in their degree of 
social achievement at the ordinal level (Isoptera), family level 
(Formicidae), and virtually the subfamily level (Vespinae), the 
Apoidea present a wide spectrum of social behavior at the generic 
level. Evidence suggests that eusociality has arisen in the bees at 
least eight times (Michener, 1962; Wilson, 1971), which may explain 
this variance. Nevertheless, it is noteworthy that of roughly 20,000 
existing species of bees only a small minority are thought to be 
presocial and eusocial (Wilson, 1971). Why sociality in the Apoidea 
7 These generic determinations are currently being reviewed by Dr. W. L. Brown, Jr. 
