diff --git a/tests/lsbase.py b/tests/lsbase.py
index 48f4186..cd5711a 100644
--- a/tests/lsbase.py
+++ b/tests/lsbase.py
@@ -71,30 +71,31 @@ def get_examples_haploid(self, ts, include_ancestors):
         return ref_panel, queries
 
     def get_examples_diploid(self, ts, include_ancestors):
-        # TODO Handle NONCOPY properly.
+        """Both the reference panel and query contain unphased genotypes."""
+        if include_ancestors is True:
+            # TODO Handle NONCOPY properly.
+            raise NotImplementedError
         ref_panel = ts.genotype_matrix()
         num_sites = ref_panel.shape[0]
-        query1 = ref_panel[:, 0].reshape(1, num_sites) + ref_panel[:, 1].reshape(
-            1, num_sites
-        )
-        query2 = ref_panel[:, -1].reshape(1, num_sites) + ref_panel[:, -2].reshape(
-            1, num_sites
-        )
-        ref_panel = ref_panel[:, 2:]
-        # Create queries with MISSING
+        # Take some haplotypes as queries from the reference panel.
+        # Note that the queries contain unphased genotypes (calculated as allele dosages).
+        query1 = ref_panel[:, 0].reshape(1, num_sites)
+        query1 += ref_panel[:, 1].reshape(1, num_sites)
+        query2 = ref_panel[:, -2].reshape(1, num_sites)
+        query2 += ref_panel[:, -1].reshape(1, num_sites)
+        # Create queries with MISSING.
         query_miss_last = query1.copy()
         query_miss_last[0, -1] = core.MISSING
         query_miss_mid = query1.copy()
         query_miss_mid[0, ts.num_sites // 2] = core.MISSING
-        query_miss_all = query1.copy()
-        query_miss_all[0, :] = core.MISSING
-        queries = [query1, query2]
-        # FIXME Handle MISSING properly.
-        # genotypes.append(s_miss_last)
-        # genotypes.append(s_miss_mid)
-        # genotypes.append(s_miss_all)
-        ref_panel_size = ref_panel.shape[1]
-        G = np.zeros((num_sites, ref_panel_size, ref_panel_size))
+        query_miss_most = query1.copy()
+        query_miss_most[0, 1:] = core.MISSING
+        queries = [query1, query2, query_miss_last, query_miss_mid, query_miss_most]
+        # Exclude the arbitrarily chosen queries from the reference panel.
+        ref_panel = ref_panel[:, 2:-2]
+        num_ref_haps = ref_panel.shape[1]   # Haplotypes, not individuals.
+        # Reference panel contains phased genotypes.
+        G = np.zeros((num_sites, num_ref_haps, num_ref_haps))
         for i in range(num_sites):
             G[i, :, :] = np.add.outer(ref_panel[i, :], ref_panel[i, :])
         return ref_panel, G, queries
diff --git a/tests/test_API.py b/tests/test_API.py
index 63b6f6e..e872a25 100644
--- a/tests/test_API.py
+++ b/tests/test_API.py
@@ -92,32 +92,32 @@ def verify(
             self.assertAllClose(B, B_vs)
             self.assertAllClose(ll_vs, ll)
 
-    @pytest.mark.parametrize("include_ancestors", [True, False])
+    @pytest.mark.parametrize("include_ancestors", [False])
     def test_ts_simple_n10_no_recomb(self, include_ancestors):
         ts = self.get_ts_simple_n10_no_recomb()
         self.verify(ts, scale_mutation_rate=True, include_ancestors=include_ancestors)
 
-    @pytest.mark.parametrize("include_ancestors", [True, False])
+    @pytest.mark.parametrize("include_ancestors", [False])
     def test_ts_simple_n6(self, include_ancestors):
         ts = self.get_ts_simple_n6()
         self.verify(ts, scale_mutation_rate=True, include_ancestors=include_ancestors)
 
-    @pytest.mark.parametrize("include_ancestors", [True, False])
+    @pytest.mark.parametrize("include_ancestors", [False])
     def test_ts_simple_n8(self, include_ancestors):
         ts = self.get_ts_simple_n8()
         self.verify(ts, scale_mutation_rate=True, include_ancestors=include_ancestors)
 
-    @pytest.mark.parametrize("include_ancestors", [True, False])
+    @pytest.mark.parametrize("include_ancestors", [False])
     def test_ts_simple_n8_high_recomb(self, include_ancestors):
         ts = self.get_ts_simple_n8_high_recomb()
         self.verify(ts, scale_mutation_rate=True, include_ancestors=include_ancestors)
 
-    @pytest.mark.parametrize("include_ancestors", [True, False])
+    @pytest.mark.parametrize("include_ancestors", [False])
     def test_ts_simple_n16(self, include_ancestors):
         ts = self.get_ts_simple_n16()
         self.verify(ts, scale_mutation_rate=True, include_ancestors=include_ancestors)
 
-    @pytest.mark.parametrize("include_ancestors", [True, False])
+    @pytest.mark.parametrize("include_ancestors", [False])
     def test_ts_larger(self, include_ancestors):
         ref_panel_size = 46
         length = 1e5
@@ -217,32 +217,32 @@ def verify(
             self.assertAllClose(ll_vs, ll)
             self.assertAllClose(phased_path_vs, path)
 
-    @pytest.mark.parametrize("include_ancestors", [True, False])
+    @pytest.mark.parametrize("include_ancestors", [False])
     def test_ts_simple_n10_no_recomb(self, include_ancestors):
         ts = self.get_ts_simple_n10_no_recomb()
         self.verify(ts, scale_mutation_rate=True, include_ancestors=include_ancestors)
 
-    @pytest.mark.parametrize("include_ancestors", [True, False])
+    @pytest.mark.parametrize("include_ancestors", [False])
     def test_ts_simple_n6(self, include_ancestors):
         ts = self.get_ts_simple_n6()
         self.verify(ts, scale_mutation_rate=True, include_ancestors=include_ancestors)
 
-    @pytest.mark.parametrize("include_ancestors", [True, False])
+    @pytest.mark.parametrize("include_ancestors", [False])
     def test_ts_simple_n8(self, include_ancestors):
         ts = self.get_ts_simple_n8()
         self.verify(ts, scale_mutation_rate=True, include_ancestors=include_ancestors)
 
-    @pytest.mark.parametrize("include_ancestors", [True, False])
+    @pytest.mark.parametrize("include_ancestors", [False])
     def test_ts_simple_n8_high_recomb(self, include_ancestors):
         ts = self.get_ts_simple_n8_high_recomb()
         self.verify(ts, scale_mutation_rate=True, include_ancestors=include_ancestors)
 
-    @pytest.mark.parametrize("include_ancestors", [True, False])
+    @pytest.mark.parametrize("include_ancestors", [False])
     def test_ts_simple_n16(self, include_ancestors):
         ts = self.get_ts_simple_n16()
         self.verify(ts, scale_mutation_rate=True, include_ancestors=include_ancestors)
 
-    @pytest.mark.parametrize("include_ancestors", [True, False])
+    @pytest.mark.parametrize("include_ancestors", [False])
     def test_ts_larger(self, include_ancestors):
         ref_panel_size = 46
         length = 1e5
diff --git a/tests/test_non_tree.py b/tests/test_non_tree.py
index b1d9d5f..fc6baee 100644
--- a/tests/test_non_tree.py
+++ b/tests/test_non_tree.py
@@ -126,32 +126,32 @@ def verify(
             self.assertAllClose(np.sum(F_tmp * B_tmp, (1, 2)), np.ones(m))
             self.assertAllClose(ll_vs, ll_tmp)
 
-    @pytest.mark.parametrize("include_ancestors", [True, False])
+    @pytest.mark.parametrize("include_ancestors", [False])
     def test_ts_simple_n10_no_recomb(self, include_ancestors):
         ts = self.get_ts_simple_n10_no_recomb()
         self.verify(ts, scale_mutation_rate=True, include_ancestors=include_ancestors)
 
-    @pytest.mark.parametrize("include_ancestors", [True, False])
+    @pytest.mark.parametrize("include_ancestors", [False])
     def test_ts_simple_n6(self, include_ancestors):
         ts = self.get_ts_simple_n6()
         self.verify(ts, scale_mutation_rate=True, include_ancestors=include_ancestors)
 
-    @pytest.mark.parametrize("include_ancestors", [True, False])
+    @pytest.mark.parametrize("include_ancestors", [False])
     def test_ts_simple_n8(self, include_ancestors):
         ts = self.get_ts_simple_n8()
         self.verify(ts, scale_mutation_rate=True, include_ancestors=include_ancestors)
 
-    @pytest.mark.parametrize("include_ancestors", [True, False])
+    @pytest.mark.parametrize("include_ancestors", [False])
     def test_ts_simple_n8_high_recomb(self, include_ancestors):
         ts = self.get_ts_simple_n8_high_recomb()
         self.verify(ts, scale_mutation_rate=True, include_ancestors=include_ancestors)
 
-    @pytest.mark.parametrize("include_ancestors", [True, False])
+    @pytest.mark.parametrize("include_ancestors", [False])
     def test_ts_simple_n16(self, include_ancestors):
         ts = self.get_ts_simple_n16()
         self.verify(ts, scale_mutation_rate=True, include_ancestors=include_ancestors)
 
-    @pytest.mark.parametrize("include_ancestors", [True, False])
+    @pytest.mark.parametrize("include_ancestors", [False])
     def test_ts_larger(self, include_ancestors):
         ref_panel_size = 45
         length = 1e5
@@ -354,32 +354,32 @@ def verify(
             self.assertAllClose(ll_tmp, path_ll_tmp)
             self.assertAllClose(ll_vs, ll_tmp)
 
-    @pytest.mark.parametrize("include_ancestors", [True, False])
+    @pytest.mark.parametrize("include_ancestors", [False])
     def test_ts_simple_n10_no_recomb(self, include_ancestors):
         ts = self.get_ts_simple_n10_no_recomb()
         self.verify(ts, scale_mutation_rate=True, include_ancestors=include_ancestors)
 
-    @pytest.mark.parametrize("include_ancestors", [True, False])
+    @pytest.mark.parametrize("include_ancestors", [False])
     def test_ts_simple_n6(self, include_ancestors):
         ts = self.get_ts_simple_n6()
         self.verify(ts, scale_mutation_rate=True, include_ancestors=include_ancestors)
 
-    @pytest.mark.parametrize("include_ancestors", [True, False])
+    @pytest.mark.parametrize("include_ancestors", [False])
     def test_ts_simple_n8(self, include_ancestors):
         ts = self.get_ts_simple_n8()
         self.verify(ts, scale_mutation_rate=True, include_ancestors=include_ancestors)
 
-    @pytest.mark.parametrize("include_ancestors", [True, False])
+    @pytest.mark.parametrize("include_ancestors", [False])
     def test_ts_simple_n8_high_recomb(self, include_ancestors):
         ts = self.get_ts_simple_n8_high_recomb()
         self.verify(ts, scale_mutation_rate=True, include_ancestors=include_ancestors)
 
-    @pytest.mark.parametrize("include_ancestors", [True, False])
+    @pytest.mark.parametrize("include_ancestors", [False])
     def test_ts_simple_n16(self, include_ancestors):
         ts = self.get_ts_simple_n16()
         self.verify(ts, scale_mutation_rate=True, include_ancestors=include_ancestors)
 
-    @pytest.mark.parametrize("include_ancestors", [True, False])
+    @pytest.mark.parametrize("include_ancestors", [False])
     def test_ts_larger(self, include_ancestors):
         ref_panel_size = 45
         length = 1e5