Ember query repeating same record over and over

I have an Ember route handler that looks like this:

import Ember from 'ember';

export default Ember.Route.extend({
  model(params) {
    return Ember.RSVP.hash({
      account: this.store.findRecord('account', params.id),
      timeZones: this.store.query('time-zone', {}),
      users: this.store.query('user', { by_account_id: params.id })
    });
  }
});

I also have a template that does this:

 each timeZones as |timeZone|
    '   ,

Even though I can tell the server is returning the right thing—149 time zones—my template just shows the last of these 149 time zones repeated 149 times.

What could be the cause of this issue?