 comment on column chronostratigraphy.upper_bound is 'Upper age boundary in years';
 create table lithostratigraphy
        (
+        id serial not null,
         group_ref classifications_ids,
         group_indexed classifications_names,
         formation_ref classifications_ids,

comment on column people_taxonomic_names.person_name is 'Person name for the group concerned';
create table chronostratigraphy
       (
        eon_ref classifications_ids,
        eon_indexed classifications_names,
        era_ref classifications_ids,

comment on column template_classifications.status is 'Validitiy status: valid, invalid, in discussion';
create table taxa
       (
        id serial not null,
        domain_ref classifications_ids,
        domain_indexed classifications_names,
        kingdom_ref classifications_ids,
