MEROZ LAB

WHAT WE'RE INTO

DYNAMICS OF PLANT BEHAVIOUR Organisms thrive in a harsh and fluctuating environment thanks to a variety of fundamental processes such as decision-making, adaptation, learning and collective behavior. These processes are based on the ability to compare environmental stimuli, either in time via memory, or in space by collectively sharing sensory information between organisms. Our lab aims to provide a mechanistic understanding of these phenomena, suggesting plant responses as a model system. We adopt a statistical physics approach, inferring underlying microscopic processes from observed macroscopic responses, and carry out experiments in house.

PHYSICS OF GROWING SYSTEMS A variety of biological systems are not motile, but sessile in nature, relying on movement resulting from continuous growth in the direction of environmental stimuli. For example, in their search for nutrients, plant roots and fungal hyphae change their morphology by growing differentially, and neuronal axons grow towards a chemical signal. The irreversible nature of growth, together with the inherent coupling between space and time, calls for a new physical description.

OUR TOOLBOX

EXPERIMENTS

We observe complex macroscopic responses of plants to diverse stimuli

STATISTICAL PHYSICS

We infer microscopic stochastic processes from macroscopic responses

MATHEMATICAL MODELING

We use minimal modeling and numerical simulations to study observations

RESEARCH AT A GLANCE

"Ask not what physics can do for biology - ask what biology can do for physics" // Ulam

temporal integration in plants Plants do not respond instantaneously but rather to an integrated history of stimuli. Together with L. Mahadevan and B. Moulia we are trying to understand memory process using theoretical and experimental tools.	plant nutations Nutation is an oscillatory movement that plants display during their development. We show that this results from the alignment of the orientation of the curvature of the plant with the direction of maximal differential growth. Bastien and Meroz (2016) PLoS Comput Biol 12	A general 3D model for growth dynamics of sensory-growth systems: from plants to robotics A general 3D model for rod-like organs, allowing to simulate key scenarios, e.g: responses to external stimuli such as a distant stimulus (such as sunlight and gravity), a point stimulus (a point light source), and a line stimulus which emulates twining of a climbing plant around a support. We also simulate circumnutations, the response to an internal oscillatory cue associated with search processes, as well as the superposition of internal and external cues.

ART >< SCIENCE

IMPOSSIBLE OBJECT

Art work in collaboration with artist Liat Segal

Part of the "Art Mission" by Rakia and the Ramon Foundation. On April 3rd 2022 Israeli astronaut Eitan Stibbe will join Ax-1, a planned SpaceX Crew Dragon mission to the International Space Station (ISS)- the first civilian mission to the ISS.

‘Impossible Object’ is a sculpture made of water. The liquid’s three-dimensional form does not get its shape from any vessel and as such cannot exist on earth, but only in space in the absence of gravity. The sculpture is built as a composition of brass rods and tubes, through which water flows. With no gravitation to direct the water downwards, the water adheres to the sculpture’s metal structure, forming a dynamic three-dimensional liquid composition, shaped by the water’s surface tension and its tendency to cling to the structure due to adhesion forces. The sculpture’s composition of rods and tubes resembles a wavy staircase that has no directionality. The work questions shape and form. In the absence of gravitation, what is the shape of a piece of sea or a handful of a wave? At times when space tourism becomes tangible rather than mostly technological and scientific, it is important to reflect on the place of culture and arts in our lives. ‘Impossible Object’ is a research-based artwork, where micro-gravity physics is the medium.

TROPISM

Art installation in collaboration with artist Liat Segal

Part of the Exhibition "Plan(e)t" @ Genia Schreiber Tel Aviv University Art Gallery | January 2020 - Jan 2022

Curators: Dr. Tamar Mayer and Dr. Sefy Hendler

A field of robotic plants is positioned at the gallery space. Inspired by natural plant behavior, the large-scale shoots slowly move in response to the changing light. Tropism, plants’ motion in response to stimuli, is expressed by the carbon-fiber mechanical shoots as they follow the artificial magenta sunrises and sunsets.