Welcome to my site!
Formally trained as an applied mathematician, I'm driven to uncover how biological systems work. Mathematics provides powerful tools for succinctly capturing the essence of a biological problem. Statistics allows extracting new knowledge from data. I apply both mathematics and statistics to ecology and biology.
Some of the problems I've worked and published on:
1) REDFIELD RATIO
One of the most expansive patterns on the Earth, spreading across oceans in the both hemispheres, is an elusive ratio of carbon (C) to nitrogen (N) to phosphorus (P), the so-called Redfield C:N:P ratio. The ratio underpins major planetary biogeochemical cycles and involves three elements central to all the known forms of life: C, N, and P. In 1934, Alfred Redfield -- a Harvard physiologist-turned-oceanographer -- empirically established a peculiar constancy between the number of N and P atoms in the deep ocean: 16 atoms of N for every atom of P. Remarkably, A. Redfield found the same ratio of N to P in the aggregate mass of phytoplankton -- a multitude of microscopic organisms that generate over half of the oxygen we breathe.
Why 16? For the last eight decades answering this question proved difficult despite mounting empirical evidence that broadly validates the pattern (even though many deviations from 16 have been found in parts of the ocean and in various plankton species). In 2011 in Ecology Letters, James Elser and I provided the first theoretical explanation for the origins of N:P=16. We showed that the N:P pattern originates on the macromolecular scale, where evolutionary fixed structures at the core of all life -- ribosomes and proteins (RNA polymerases) -- are innately inter-depended on each other's biosynthesis.
The next question is how does this atomic pattern stemming from the subcellular and macromolecular scales, propagates to the global scale? In 2010, I developed a model answering this question but has not published the proof yet. However, this year, I published a mathematical framework called, Iterative Chemostat, that links the synthesis of information bearing biopolymers (nucleic acids and proteins) to nutrient cycling.
The framework sets the stage for proving Alfred Redfield's original hypothesis that one of the largest stoichiometric patterns on the planet originates from the inner workings of one of the smallest living structures - a photosynthetic cell.
2) RISING CO2 & HUMAN NUTRITION
In late 1990s, while working on my PhD in Mathematics, I was fortunate to be exposed to the theory of Ecological Stoichiometry in James Elser's lab. The theory allowed me to deduce that rising CO2 should result in a global depletion of essential minerals in the tissues of plants, including edible tissues such as grains. More importantly, the theory enabled me to link this nutrient depletion to human nutrition.
In 2002, I published a hypothesis that rising atmospheric CO2 levels should "intensify the already acute problem of micronutrient malnutrition". Because Iron (Fe), Zinc (Zn) and Iodine (I) had already been deficient in the human diet, these nutrients got a special focus in my paper.
Unfortunately, the published experimental data in 2002 were very limited to validate the hypothesis empirically. It took me about 12 years to compile enough evidence from CO2 experiments run by dedicated researchers in Australia, Asia, Europe, and the United States to prove that, indeed, rising CO2 depletes minerals at the base of human nutrition -- plants.
The meta-analysis in my 2014 paper showed that the levels of essential minerals, including calcium (Ca), copper (Cu), iron (Fe), magnesium (Mg), phosphorus (P) and zinc (Zn), decline in a broad range of crops and wild plants (called C3 plants), and that this mineral depletion is geographically pervasive and systemic throughout plant tissues. This discovery was made possible by all the pertinent data coming from experiments that grew plants under elevated CO2 and controlled conditions run by hundreds of researchers. Their collective efforts generated enough data (I have compiled 7,761 pairs of observations, i.e. over 15,000 observations) to reveal the hidden shift in the quality of plants caused by increasing levels of carbon dioxide.
Furthermore, I theorize that this downshift in the plant quality that is undergoing on the planetary scale is worsening not only mineral undernutrition but also calorie overnutrition, i.e. it is contributing to both the 'hidden hunger' & obesity.
This year, with colleagues from Ireland, Columbia University and Bryan, we published new findings about the decline of carotenoids -- vital for eye and brain health -- in plant tissues exposed to elevated CO2.
Any questions or comments? Email: loladze@gmail.com (this is my prefered email rather than my Bryan work email)
I usually reply within 24 hours. If urgent, please, let me know in the subject of the email, and I'll respond ASAP: loladze@gmail.com
You are also welcome to DM me @twitter: @loladze