Multi-Messenger Astronomy with Extremely Large Telescopes

The field of time-domain astrophysics has entered the era of Multi-messenger Astronomy (MMA). One key science goal for the next decade (and beyond) will be to characterize gravitational wave (GW) and neutrino sources using the next generation of Extremely Large Telescopes (ELTs). These studies will have a broad impact across astrophysics, informing our knowledge of the production and enrichment history of the heaviest chemical elements, constrain the dense matter equation of state, provide independent constraints on cosmology, increase our understanding of particle acceleration in shocks and jets, and study the lives of black holes in the universe. Future GW detectors will greatly improve their sensitivity during the coming decade, as will near-infrared telescopes capable of independently finding kilonovae from neutron star mergers. However, the electromagnetic counterparts to high-frequency (LIGO/Virgo band) GW sources will be distant and faint and thus demand ELT capabilities for characterization. ELTs will be important and necessary contributors to an advanced and complete multi-messenger network.Comment: White paper submitted to the Astro2020 Decadal Surve

The ancient Levantine Botryllus schlosseri (Tunicata): population genetics landscape under frequent natural disturbances

The colonial ascidian Botryllus schlosseri is a cosmopolitan species, commonly found in sheltered temperate marine environments, primarily marinas/harbors. B. schlosseri larvae settle immediately upon release on hard substrates in vicinity (<50cm) to maternal colonies, suggesting genetically structured populations on fine spatial scales. By employing seven microsatellite loci, this study characterizes long-term (2004-2008) genetic structures of a B. schlosseri population residing underneath stones at Michmoret harbor, the Israeli Mediterranean coast, revealing a persistence of genetic structure through time. Further, the Michmoret harbor was exposed to episodes of natural disturbances (October 2006 and November 2007), during which the entire populations were eradicated from shallow waters. These disturbances provide a unique opportunity to study the population genetic dynamics of newly established populations of a marine invasive species, within its geographic origin. The results revealed a four year-long structured single population in Michmoret harbor, homogeneous at the time but not at the micro-geographic scales. The B. schlosseri population from Michmoret harbor, unlike other populations of B. schlosseri worldwide, showed no genetic changes such as changes in the distribution of allele frequencies that were reported in other B. schlosseri populations after natural catastrophic events

The arrival of a second ‘Lessepsian sprinter’? A first record of the red cornetfish Fistularia petimba in the Eastern Mediterranean

Here we document the first occurrence of the red cornetfish Fistularia petimba in the Levantine Basin. This species identity has been confirmed using morphological and molecular tools, and is presented here with simplified illustrations for accurate future identification. This report voices a concern regarding another blitz invasion of a cornetfish into the Mediterranean, following its Lessepsian sprinter congeneric, F. commersonii, one of the most efficacious invaders of the Mediterranean Sea. The wide intra-specific genetic distances found between sympatric F. petimba specimens in the available literature resources may also demonstrate the presence of cryptic diversity within this taxon

Native, invasive and cryptogenic Ulva species from the Israeli Mediterranean Sea: risk and potential

The genus Ulva (Chlorophyta) is ubiquitous along Israeli Mediterranean shores where it has been studied extensively due to its important ecological role and potential value in biotechnology and aquaculture. Previous identifications of Ulva in Israel were based only on morphology. Here, we compare species found in 2002 and in 2014-2016. Analyses of ribulose-1,5-bisphosphate carboxylase/oxygenase (rbcL) and elongation factor 1-alpha (tufA) plastid genes (2014-2016 samples only), combined with morphological data, identified six Ulva species, three of which are new records for Israel and probably originate from the Indo-Pacific. Ulva compressa, rarely found in 2002, is now the most abundant species and exhibits two fairly distinct morphologies correlated with different haplotypes for both genes.  Ulva fasciata was found more commonly in 2002 than in 2014-16, whereas the morphologically similar, and closely related, invasive species U. ohnoi seemed more frequent in recent samples.  The finely branched tubular Ulva tepida was found in 2002 and 2015/16, and U. chaugulii and U. mediterranea were discovered for the first time in 2015/16.  The changing Ulva flora of the Israeli Mediterranean may be correlated with major environmental changes including 3°C increase in sea surface temperatures over the last two decades, as well as a generally increasing prevalence of non-native species.  The local Ulva species now found in Israel could be of value for various industrial uses

Portion coherence: enhancing the relevance of introductory courses in teacher education

Studies investigating coherence in teacher preparation often attempt to achieve comprehensive coherence across all components of training to optimize the educational process. Nevertheless, the pursuit of intense coherence presents notable challenges. To address these challenges, we propose the concept of portion coherence, exemplified by the Trio model, which guides pre-service teachers in integrating theories into their practices. Through a mixed-method study, we compared pre-service teachers’ perceptions of the importance and relevance of introductory courses at the semester’s outset and conclusion. While both groups reported a reduction in perceived importance, the intervention group noted a significantly smaller decline in perceived relevance compared to the control group. This suggests that models of portion coherence may enhance the perceived relevance of educational courses, while the perceived relevance of introductory education courses may serve as an indicator of cross-course coherence

Initiating DNA barcoding of Eastern Mediterranean deep-sea biota

Preliminary results of DNA barcoding survey of deep-sea mega-faunal biota are presented, collected by trawl and gillnet off the Israeli coast (SE Mediterranean, depths 700 to 1500 meters) during 2012-2013. 846 organisms were identified to 37 species, mainly fish and decapod crustaceans. The most abundant species were the blackmouth catshark Galeus melastomus, the cosmopolitan decapod Polycheles typhlops and the bivalve Abra longicallus. Two species were sampled for the first time from the southern Levant- the long armed chiroteuthid squid Chiroteuthis veranyi and the common mora, Mora moro. Four of the 18 fish species and two of the 10 crustacean species were abundant, representing 78% and 61%, respectively, of the organisms collected. Most other species are represented by fewer than 10 individuals. PCR products for the cytochrome c oxidase sub unit I (COI) gene for the 37 species were successfully sequenced. The identified and vouchered individuals are stored at the Steinhardt Museum of Natural History (Tel Aviv University, Israel) and their COI sequences were uploaded into the BoLD universal data center as part of the national marine barcoding project. The COI sequences of Acanthephyra eximia, Gryphus vitreus, Galeodea echinophora, Mesothuria intestinalis and Astropecten irregularis, constitute first records of these species in BoLD. When compared to the COI sequences in BoLD, the present results reveal some inconsistency in species identification, an outcome that should be taken into consideration primarily once the taxonomical verifications of collected taxa are elusive. This study is the first step in DNA barcoding of the Levant’s little-known benthic deep-sea fauna