Prof. Achituv's Lab
Environmental and Global Research of Aquatic Systems
Prof. (Emeritus) Yair Achituv, of the Mina and Everard Goodman Faculty of Life Sciences,uses molecular tools to answer ecological and behavioral questions in marine biology, with a specific focus on invertebrates.
Achituv, in collaboration with Dr. Oren Levy, are studying the behavior and underlying molecular mechanisms of intertidal animals, with regard to their timing of activity, as it is set by endogenous biological clocks. The model organism is a limpet, (marine snail), commonly found on rocky shores. Achituv and Levy’s group is conducting a study on two levels – behavioral and molecular. Using non-invasive methods, mostly video recording, they are quantifying limpet behavior under different experimental conditions and manipulations (light, temperature, artificial tide) in a designated "wet" laboratory. On a molecular level, they are attempting to find known circadian (daily) clock genes in order to elucidate their rhythm of expression as a function of the time of day and tidal phase. In addition, they are trying to identify novel genes that may be unique to tidal clock mechanisms (as against circadian clocks).
The Balanomorpha (Crustacea: Thoracica: Sessilia) is the most diverse group of barnacles with more than 1000 species distributed in 12 families and ~100 genera.
They rank among the most commonly encountered marine crustaceans in the world and have been present in the fossil record since the Cretaceous. Balanomophan are prime models for studies on intertidal ecology, larval settlement, antifouling technology and for testing theories on the evolution of life cycles and reproductive systems.
Relationships among the main Balanomorpha groups are poorly understood and the phylogeny of some charismatic groups, such as the Balanoidea, is unresolved. Achituv's research team is currently conducting the first comprehensive study of Balanomorpha evolution using a phylogenetic approach in 200 years. Their study is a landmark in barnacle systematics, as it will provide a new phylogenetic framework for classifying the Balanomorpha barnacles reflecting evolutionary relationships. It is being conducted in collaboration with colleagues from Denmark, Portugal, the US and Japan.
In the Footsteps of Connell: Using Molecular Tools for Revealing Patterns of Intertidal Zonation
Connell’s study of the interspecific competition mechanism between two cirripedes species, conducted fifty years ago, is considered a pioneering work in the field of ecology, since it used controlled experimental manipulations of populations in a natural field situation.
Achituv's research team has conducted a study aimed at understanding the zonation pattern dynamics, in space and time, of two common intertidal Mediterranean cirripede species:Chthamalus stellatus, which is dominant over the lower belt, and Euraphia depressa, which occupies the higher belt at the uppermost intertidal level, but is also common on bottom-facing surfaces. In their research work, they have addressed the following questions: Are the settlement mechanisms specific or random? At what point in the recruitment process is zonation created, and by which factors?
Using Connell’s experimental methods, they mapped the dispersal patterns of adult populations at four sites in Israel: Akhziv, Shikmona, Habonim and Palmachim. Settlement and recruitment were assessed using standardized double-sided settlement plates, at sampling intervals of a day, two weeks and one month, from Aug 2009 and Dec 2010. After performing manipulation experiments of belt-shifting and exposure, the group counted, measured, and analyzed the settling individuals. Working around the species identity problem, they developed a discriminating system based on PCR with species-specific primers using 16S mt rDNA.