If we knew what we were doing, it would not be called research, would it?
- Albert Einstein
Sexual reproduction in marine invertebrates
Sexual reproduction, the primary process of generating new genetic lineages, is fundamental to our understanding of biodiversity, biogeography and evolution at large. Yet, as global warming and climate-change proceeds ever more rapidly, organisms depending on seasonal cues to synchronize their reproduction, face an unclear future.
We are particularly interested in studying sexual reproduction of broadcast spawning marine invertebrates - from the environmental regulation of gametogenesis and spawning, through fertilization dynamics and hybridization, to gamete incompatibility and reproductive barriers.
Echinoderms as model organisms
Echinoderms comprise one of the most prominent and wide-spread groups of benthic marine invertebrates. Distributed across all of the world's oceans, from the poles to the equator and from the abyssal to intertidal depths, they constitute one of the most ecologically significant components of diverse marine environments.
Comprising of roughly 7000 living species, echinoderms are the second-largest group of deuterostomes, strategically situated at the base of the evolutionary split leading to vertebrates. This unique evolutionary setup coupled with their fundamental ecological role, turns echinoderms into primary research model organisms.
Reproductive dynamics of
broadcast spawners revealed through environmental DNA
(ISF grant 2407/20)
Sexual reproduction, the primary process of generating new genetic lineages, is fundamental to our understanding of biodiversity, biogeography and evolution at large. Yet, as global warming and climate-change proceeds ever more rapidly, organisms depending on seasonal cues to synchronize their reproduction, face an unclear future.
We are particularly interested in studying sexual reproduction of broadcast spawning marine invertebrates - from the environmental regulation of gametogenesis and spawning, through fertilization dynamics and hybridization, to gamete incompatibility and reproductive barriers.
Ecology and evolution of edible sea urchins
(FWF grant 2407/20)
Sea urchins of the order Camarodonta are among the most important components of shallow-water marine communities. They are intensively used models-species for developmental studies and are the prime target of a multimillion-dollar fisheries industry. Despite of the wealth of studies on various aspects of their biology and life histories, the evolutionary history and diversification of Camarodonta is poorly understood and their phylogeny remains poorly resolved.
Here we aim to decipher the origin and evolutionary history of camarodont sea urchins. To achieve this goal, genetic information at the genome level, is combined with an in depth morphological analysis. This will allow incorporation of fossil taxa with modern species in order to gain insights into camarodont radiation and identify basal crown-group members of modern families.
This research is carried out in collaboration with Andreas Kroh and Elisabeth Haring from the Natural History Museum (NHM) Vienna, Austria with the help of an international team of expert collaborators team.
Creating biological baselines and monitoring protocols for marine reserves in the Israeli Mediterranean Sea
(NPA/Yad Hanadiv grant 10699)
Comprehensive biological baselines are fundamental for the development of robust monitoring programs that facilitate effective management. In particular, accurate assessment of biodiversity is an essential component in designing marine protected areas and maintaining ecosystem function. Current gaps in knowledge limit our ability to design robust, long-term monitoring protocols and implement appropriate management measures. As the Israel Nature and Parks Authority (INPA) aim to establish a network of large marine reserves in at least 20% of the Israeli Mediterranean, and as deterioration of coastal marine environments is proceeding ever more rapidly, the need for comprehensive baseline data on which to build an effective monitoring program, is greater than ever before.
Here we aim to generate biological baselines for the marine nature reserves along the Israeli Mediterranean and design effective monitoring protocols. Selected taxa, from a wide range of trophic levels, will be tested for their suitability to serve as sensitive, long-term monitoring proxies. We develop an integrated system comprising of a wide array of novel methodologies, from deep sea acoustics, through deployment of 3D monitoring platforms, to molecular genetics.
Scanning Electron Microscope (SEM)
We use the Phenom XL desktop SEM to inspect the micro-structures of small skeletal objects such as platelets, spicules, and pedicellariae from a verity of organisms.
Uniquely designed to handle large size samples, this device is quipped with a 10x10 cm rotating stage, eliminating the need for destructive sample preparation of rare and precious samples.
A gold (Au) Sputter Coater complements our SEM platform.
Computer-Aided Sperm Analyser
(CASA)
Computer-Aided Sperm Analysis (CASA) system facilitates the quantitative and qualitative analysis of sperm characteristics and performance such as sperm concentration and motility. This system is mounted on a Nikon Eclipse Ci-L microscope built with phase-contrast optics.
We use the Sperm Class Analyzer (SCA) by Microptic for accurate, repetitive and automatic assessment of sperm: concentration, motility, vitality, morphology, DNA fragmentation and acrosome reaction.
Molecular Lab
We conduct a verity of molecular pipelines from DNA extraction, PCR amplifications and NGS applications from a wide range of marine invertebrates.
Using cutting-edge technologies of molecular biology, such as meta-barcoding and eDNA analyses, our inhouse molecular facilities include UV sterilized cabinets, PCR machines, Qubit fluorometer, gel electrophoresis and imaging systems.
Histology Lab
We routinely perform histological analyses to identify structures and ongoing processes at the cellular level in tissues from a verity of marine invertebrates, with a main focus on reproductive development.
Operating the Histological Unit of the School of Zoology (Tel Aviv University), our facilities cover all stages from sample preparation, embedding, sectioning and staining.
Microscopy & Imaging
A picture is worth a 1000 words, they say.
We operate a wide range of high resolution imaging and documentation platforms to capture the fine details of our subjects of interest.
We use a Nikon D850 camera equipped with high definition macro lenses mounted on a Kaiser RS1 Copy Stand with RB5070DX2 lighting unit for macro photography.
A motorized, fluorescence Nikon Eclipse Ni-E Microscope, topped with the high resolution Nikon DS-Ri2 camera is used as our main optical platform.
Complementing our microscopy array is a Nikon SMZ18 Stereomicroscope topped with a Nikon DS-Fi3 camera.
Field Station & Diving
As marine biologists and ecologists our research involves extensive field work. Our students are trained in a wide set of skills needed for pursuing their studies. These include technical SCUBA diving, underwater photography, Nitrox, Trimix and closed circuit rebreather diving.
While working across the entire Indo-Pacific, from the Western Indian Ocean to Japan and Australia, our 'back yard' marine playground includes the Mediterranean Sea and Gulf of Aqaba at the northern Red Sea.
