Evolution and relationships of the conifer seed cone telemachus: Evidence from the triassic of antarctica

The seed cone Telemachus is known from several Triassic localities in Gondwana. New specimens from two localities in Antarctica provide additional information about the type species, Telemachus elongatus, based on details of morphology and anatomy revealed by using a modified transfer technique on the compressed plants. Seed cones of T. elongatus are up to 6.0 cm long and characterized by conspicuous, elongate bracts. A second Antarctic species, described here as Telemachus antarcticus, is segregated, based on a shorter bract and differences in cone size. Newly recognized features of the genus include the shape, size, and disposition of the ovules; vascularization of the ovuliferous complex; and scale and bract histology. As a result of this new information, it is now possible to compare Telemachus with the permineralized Middle Triassic conifer seed cone Parasciadopitys from the Central Transantarctic Mountains. The similarities between the two genera make it possible to relate organs in different preservational modes and to develop a more complete concept for this widely distributed Gondwana conifer. Placing the Telemachus plant within a phylogenetic context makes it possible to evaluate the relationship with other so-called transitional conifers, an informal group that has been interpreted as intermediate between Paleozoic and modern conifers.Fil: Escapa, Ignacio Hernán. University of Kansas; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Decombeix, Anne-Laure. University of Kansas; Estados UnidosFil: Taylor, Edith L.. University of Kansas; Estados UnidosFil: Taylor, Thomas N.. University of Kansas; Estados Unido

Secondary Growth in Vertebraria Roots from the Late Permian of Antarctica: A Change in Developmental Timing

This is the publisher's version, also available electronically from http://www.jstor.org/stable/10.1086/597784.Permineralized Vertebraria roots from the late Permian of the Central Transantarctic Mountains, Antarctica, are investigated to understand the unusual vascular anatomy of the genus. The specimens range from ∼1 mm to several centimeters in diameter and illustrate all the stages of secondary growth. Our observations confirm previous hypotheses on the development of these roots and suggest that their unique anatomy is the result of a change in developmental timing. Vertebraria is characterized by a vascular cambium that remains discontinuous through several growth seasons, leading to the formation of lacunae alternating in cross section with wedges of secondary vascular tissues. The bifacial nature of the cambium is confirmed by the presence of well‐developed secondary phloem composed of longitudinally elongated cells and uniseriate parenchymatous rays. In some of the largest specimens, a continuous vascular cylinder is formed by the differentiation of cambium from parenchymatous cells bordering the lacunae. The new specimens provide additional information on the secondary xylem anatomy and vascular connection to lateral roots

Dordrechtites Arcanus Sp. Nov., An Anatomically Preserved Gymnospermous Reproductive Structure From the Middle Triassic of Antarctica

This is the publisher's version of an article which is being shared with permission. The original version may be accessed at: http://dx.doi.org/10.1086/668792The genus Dordrechtites is an isolated ovulate structure previously described only from South Africa and Australia as impressions. The discovery of compressed and permineralized specimens of this taxon at the base of Mount Falla (uppermost Fremouw Formation) in the central Transantarctic Mountains extends the geographical and geological distribution of the genus and increases the known floral diversity of the Triassic of Antarctica. The first permineralized species, Dordrechtites arcanus, is described using standard acetate peel techniques and includes internal anatomy of an elongate arm that extends over the top of a central cupule containing two elongate, bilaterally symmetrical, orthotropous ovules. An arc-shaped collateral vascular bundle extends from the arm into the top of the cupule, branches, and then extends around the ovule to about halfway down to the micropylar end. The cupule is parenchymatous and includes transfusion tissue with cells that have pitted walls. The sclerotesta of the ovule is up to 200 mm thick, consisting of an outer layer with longitudinally oriented, thick-walled cells and an inner layer one cell thick of rectangular, thick-walled cells. The micropyle is flared at the attenuated tip of the pyramidal cupule. The four previously described species of Dordrechtites have uncertain affinities, and although the morphology and anatomy of this taxon is now known, the affinities within the gymnosperms are still uncertain

Epicormic Schoots in a Permian Gymnosperm from Antarctica

This is the publisher's version. Shared with permission, it is also available electronically from: http://dx.doi.org/10.1086/654849Two anatomically preserved gymnosperm trunks with clusters of epicormic shoots are described from the Late Permian of Antarctica. The best-preserved trunk is 14 cm long. It has a small circular parenchymatous pith and 9 cm of secondary xylem that contains at least 50 growth rings. The second specimen is slightly smaller (11 3 8 cm) and has 20 growth rings. Both specimens have pycnoxylic wood and produced more than 50 small shoots in a delimited zone on the surface of the trunk. Shoots have a wide parenchymatous pith that may be solid to septate with endarch primary xylem forming 8–10 sympodia and a small amount of secondary xylem similar to that of the parent trunk. The shoots branch and increase in number toward the outside of the trunk. Evidence based on anatomical comparisons and association at the site indicates that the specimens probably represent trunks of some glossopterid, the dominant group of seed ferns during the Permian in Gondwana. This is the first report of clusters of epicormic shoots in a Paleozoic gymnosperm. The ability to produce a large number of young shoots that were capable of developing into new branches indicates that these high-latitude trees possessed an architectural plasticity that allowed them to respond quickly to short- or longterm environmental stress

Clery Act Needs Whistleblower Protection

In light of the apparent cover-up by the leadership at Eastern Michigan University (EMU) of a student rape and murder on campus, Congress should amend the Jeanne Clery Act. Specifically, a whistleblower protection section needs to be added to this landmark sunshine law

Lock & Load? The 2nd Amendment Arrives on Campus

Thanks to the U.S. Supreme Court’s watershed decision regarding the Second Amendment in June, state lawmakers, university policymakers and campus safety personnel nationwide face a conundrum that must be answered in a prudent way. The solution will greatly impact the daily lives of everyone on campus

Evolution and Relationships of the Conifer Seed Cone Telemachus: Evidence from the Triassic of Antarctica

This is the publisher's version, also available electronically from http://www.jstor.org/stable/10.1086/651948The seed cone Telemachus is known from several Triassic localities in Gondwana. New specimens from two localities in Antarctica provide additional information about the type species, Telemachus elongatus, based on details of morphology and anatomy revealed by using a modified transfer technique on the compressed plants. Seed cones of T. elongatus are up to 6.0 cm long and characterized by conspicuous, elongate bracts. A second Antarctic species, described here as Telemachus antarcticus, is segregated, based on a shorter bract and differences in cone size. Newly recognized features of the genus include the shape, size, and disposition of the ovules; vascularization of the ovuliferous complex; and scale and bract histology. As a result of this new information, it is now possible to compare Telemachus with the permineralized Middle Triassic conifer seed cone Parasciadopitys from the Central Transantarctic Mountains. The similarities between the two genera make it possible to relate organs in different preservational modes and to develop a more complete concept for this widely distributed Gondwana conifer. Placing the Telemachus plant within a phylogenetic context makes it possible to evaluate the relationship with other so‐called transitional conifers, an informal group that has been interpreted as intermediate between Paleozoic and modern conifers

Curriculum implementation exploratory studies: Final report

Throughout the history of schooling in New Zealand the national curriculum has been revised at fairly regular intervals. Consequently, schools are periodically faced with having to accommodate to new curriculum. In between major changes other specifically-focused changes may arise; for example, the increased recent emphasis upon numeracy and literacy