Cristian A. Solari

• PhD
• Founder at SpeciesConnect

Interactions between different species are known as interspecies interactions. All aspects of life depend on interspecies interactions. Ever since the dawn of life on Earth, species have been competing for resources, eating or being eaten, parasitizing, and collaborating with each other. Even the eukaryote cell, which is the most basic unit of all...

Although there is a well developed theory on the relationship between the intrinsic growth rate r and temperature T, it is not yet clear how r relates to abundance, and how abundance relates to T. Many species often have stable enough population dynamics that one can talk about a stochastic equilibrium population size N*. There is sometimes an assu...

The volvocine green algae have been extensively used to address various questions related to the evolution of multicellularity and cell differentiation, in terms of the genetics, developmental constraints, and underlying selective forces specific to this group. More recently, physical characteristics of the environment and of the emerging multi-cel...

The volvocine green algae in the order Volvocales are an ideal modelsystem for studying the unicellular-multicellular transition since they comprise an assemblage of lineages featuring varying degrees of complexity in terms of colony size, colony structure, and cellular specialization. Here, we have investigated the size-related advantages that mig...

Abstract The transition from unicellular, to colonial, to larger multicellular organisms has benefits, costs, and requirements. Here we present a model inspired by the volvocine green algae that explains the dynamics involved in the unicellular-multicellular transition using life-history theory and allometry. We model the two fitness components (fe...

Steering their swimming direction toward the light is crucial for the viability of Volvox colonies, the larger members of the volvocine algae. While it is known that this phototactic steering is achieved by a difference in behavior of the flagella on the illuminated and shaded sides, conflicting reports suggest that this asymmetry arises either fro...

Flagella-generated fluid stirring has been suggested to enhance nutrient uptake for sufficiently large micro-organisms, and to have played a role in evolutionary transitions to multicellularity. A corollary to this predicted size-dependent benefit is a propensity for phenotypic plasticity in the flow-generating mechanism to appear in large species...

Volvox barberi W. Shaw is a volvocalean green alga composed of biflagellated cells. Vovocales with 16 cells or more form spherical colonies, and their largest members have germ-soma separation (all species in the genus Volvox). V. barberi is the largest Volvox species recorded in terms of cell number (10,000–50,000 cells) and has the highest somati...

A fundamental issue in evolutionary biology is the transition from unicellular to multicellular organisms, and the cellular differentiation that accom- panies the increase in group size. Here we consider recent results on two types of ''multicellular'' systems, one produced by many unicellular organisms acting collectively, and another that is perm...

Evolution from unicellular organisms to large, multicellular ones requires matching their needs to the rate of exchange of molecular nutrients with the environment. This logistic problem poses a severe constraint on development. For organisms whose body plan is a spherical shell, such as the volvocine green algae, the current of needed nutrients gr...

Evolution from unicellular organisms to larger multicellular ones requires matching their needs to the rate of exchange of molecular nutrients with the environment. This logistic problem poses a severe constraint on development. For organisms whose body plan is a spherical shell, such as the volvocine green algae, the current (molecules per second)...

During the unicellular-multicellular transition, there are opportunities and costs associated with larger size. We argue that germ-soma separation evolved to counteract the increasing costs and requirements of larger multicellular colonies. Volvocalean green algae are uniquely suited for studying this transition because they range from unicells to...

During the unicellular-multicellular transition, there are opportunities and costs associated with larger size. We argue that germ-soma separation evolved to counteract the increasing costs and requirements of larger multicellular colonies. Volvocalean green algae are uniquely suited for studying this transition because they range from unicells to...

The fitness of an evolutionary individual can be understood in terms of its two basic components: survival and reproduction. As embodied in current theory, trade-offs between these fitness components drive the evolution of life-history traits in extant multicellular organisms. Here, we argue that the evolution of germ-soma specialization and the em...

Benefits, costs, and requirements accompany the transition from motile totipotent unicellular organisms to multicellular organisms having cells specialized into reproductive (germ) and vegetative (sterile soma) functions such as motility. In flagellated colonial organisms such as the volvocalean green algae, organized beating by the somatic cells'...

The evolution of single cells to large and multicellular organisms requires matching the organisms' needs to the rate of exchange of metabolites with the environment. This logistic problem can be a severe constraint on development. For organisms with a body plan that approximates a spherical shell, such as colonies of the volvocine green algae, the...

The Volvocales constitute a family of colonial algae ranging in size from tens to hundreds of microns. The surface of these nearly spherical algae is packed with cells, each having two flagella. Their incessant, periodic flailing moves the water in which the organisms live. The Volvocales and especially their largest member Volvox constitute a mode...

Abstract