The genus Tsuga is comprised of eight extant species found in North America and East Asia and four species represented by fossils from Europe and Japan. This study presents the first phylogenetic analysis based on structural, biochemical, and molecular sequence data. Characters obtained from published and unpublished literature were combined with new morphological characters from seeds, seedlings, and leaf cuticle material. Results from parsimony analyses of these characters differed from the published molecular based phylogeny. The non-molecular based phylogeny resolves two separate clades, a North American and an Asian, but did not group the western North American species, as in the molecular based analysis. Character states were traced on the trees to interpret character evolution. The combined analysis resulted in a phylogeny that differed from the previously published molecular tree by resolving a clade between T. caroliniana and T. diversifolia and placing T. dumosa outside of the Asian clade.
","abstract_html":"<p>The genus <em>Tsuga</em> is comprised of eight extant species found in North America and East Asia and four species represented by fossils from Europe and Japan. This study presents the first phylogenetic analysis based on structural, biochemical, and molecular sequence data. Characters obtained from published and unpublished literature were combined with new morphological characters from seeds, seedlings, and leaf cuticle material. Results from parsimony analyses of these characters differed from the published molecular based phylogeny. The non-molecular based phylogeny resolves two separate clades, a North American and an Asian, but did not group the western North American species, as in the molecular based analysis. Character states were traced on the trees to interpret character evolution. The combined analysis resulted in a phylogeny that differed from the previously published molecular tree by resolving a clade between <em>T. caroliniana</em> and <em>T. diversifolia</em> and placing <em>T. dumosa</em> outside of the Asian clade.</p>","abstract_has_math":false,"creators":["Baker, Jordan David"],"institution":null,"degree_name":"MS (Master of Science)","degree_level":"Thesis - unrestricted","degree_discipline":"Biology","degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2009,"date_issued":"2009-08-19T07:00:00Z","date_published":"2009-08-19T07:00:00Z","updated_at":"2026-07-24T02:20:55Z","subjects":["Morphological Characters","Phylogenetic Analysis","Leaf Cuticle","Tsuga","Phylogeny","Morphology","Seedlings","Seed","Earth Sciences","Paleobiology","Physical Sciences and Mathematics"],"languages":[],"rights":["Copyright by the authors."],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://dc.etsu.edu/etd/1791","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Baker, Jordan David"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.issued","label":"Date","values":["2009-08-19T07:00:00Z"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Biology"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis - unrestricted"]},{"key":"thesis:degree_name","label":"Degree Name","values":["MS (Master of Science)"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Morphological Characters","Phylogenetic Analysis","Leaf Cuticle","Tsuga","Phylogeny","Morphology","Seedlings","Seed","Earth Sciences","Paleobiology","Physical Sciences and Mathematics"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:rights","label":"Dc Rights","values":["Copyright by the authors."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://dc.etsu.edu/context/etd/article/3143/viewcontent/BakerJ051909f.pdf","https://dc.etsu.edu/etd/1791"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["The genus Tsuga is comprised of eight extant species found in North America and East Asia and four species represented by fossils from Europe and Japan. This study presents the first phylogenetic analysis based on structural, biochemical, and molecular sequence data. Characters obtained from published and unpublished literature were combined with new morphological characters from seeds, seedlings, and leaf cuticle material. Results from parsimony analyses of these characters differed from the published molecular based phylogeny. The non-molecular based phylogeny resolves two separate clades, a North American and an Asian, but did not group the western North American species, as in the molecular based analysis. Character states were traced on the trees to interpret character evolution. The combined analysis resulted in a phylogeny that differed from the previously published molecular tree by resolving a clade between T. caroliniana and T. diversifolia and placing T. dumosa outside of the Asian clade.
"]},{"key":"dc:title","label":"Title","values":["A Phylogenetic Analysis of Species Relationships in Hemlocks, the Genus Tsuga (Pinaceae)."]}]}],"canonical_facts":{"dc:creator":["Baker, Jordan David"],"dc:date.issued":["2009-08-19T07:00:00Z"],"dc:description.abstract":["The genus Tsuga is comprised of eight extant species found in North America and East Asia and four species represented by fossils from Europe and Japan. This study presents the first phylogenetic analysis based on structural, biochemical, and molecular sequence data. Characters obtained from published and unpublished literature were combined with new morphological characters from seeds, seedlings, and leaf cuticle material. Results from parsimony analyses of these characters differed from the published molecular based phylogeny. The non-molecular based phylogeny resolves two separate clades, a North American and an Asian, but did not group the western North American species, as in the molecular based analysis. Character states were traced on the trees to interpret character evolution. The combined analysis resulted in a phylogeny that differed from the previously published molecular tree by resolving a clade between T. caroliniana and T. diversifolia and placing T. dumosa outside of the Asian clade.
"],"dc:identifier":["https://dc.etsu.edu/context/etd/article/3143/viewcontent/BakerJ051909f.pdf","https://dc.etsu.edu/etd/1791"],"dc:rights":["Copyright by the authors."],"dc:subject":["Morphological Characters","Phylogenetic Analysis","Leaf Cuticle","Tsuga","Phylogeny","Morphology","Seedlings","Seed","Earth Sciences","Paleobiology","Physical Sciences and Mathematics"],"dc:title":["A Phylogenetic Analysis of Species Relationships in Hemlocks, the Genus Tsuga (Pinaceae)."],"thesis:degree_discipline":["Biology"],"thesis:degree_level":["Thesis - unrestricted"],"thesis:degree_name":["MS (Master of Science)"]},"updated_at":"2026-07-24T02:20:55Z"}