A mathematical model for the phase of sexual reproduction in monogonont rotifers

Angel Calsina; José M. Mazón; Manuel Serra

doi:10.1007/s002850000021

Limited Dispersal, Deleterious Mutations and the Evolution of Sex

Genetics ◽

10.1093/genetics/142.3.1053 ◽

1996 ◽

Vol 142 (3) ◽

pp. 1053-1060

Author(s):

Joel R Peck

Keyword(s):

Mathematical Model ◽

Sexual Reproduction ◽

Genetic Locus ◽

Genetic Material ◽

Plant Population ◽

Deleterious Mutations ◽

Animal Populations ◽

Offspring Sex ◽

Limited Dispersal ◽

Hermaphroditic Plant

Abstract This study presents a mathematical model that allows for some offspring to be dispersed at random, while others stay close to their mothers. A single genetic locus is assumed to control fertility, and this locus is subject to the occurrence of deleterious mutations. It is shown that, at equilibrium, the frequency of deleterious mutations in the population is inversely related to the rate of dispersal. This is because dispersal of offspring leads to enhanced competition among adults. The results also show that sexual reproduction can lead to a decrease in the equilibrium frequency of deleterious mutations. The reason for this relationship is that sex involves the dispersal of genetic material, and thus, like the dispersal of offspring, sex enhances competition among adults. The model is described using the example of a hermaphroditic plant population. However, the results should apply to animal populations as well.

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Transgenerational plasticity for sexual reproduction and diapause in the life cycle of monogonont rotifers: intraclonal, intraspecific and interspecific variation in the response to crowding

Functional Ecology ◽

10.1111/j.0269-8463.2004.00854.x ◽

2004 ◽

Vol 18 (3) ◽

pp. 458-466 ◽

Cited By ~ 53

Author(s):

T. SCHRODER ◽

J. J. GILBERT

Keyword(s):

Life Cycle ◽

Sexual Reproduction ◽

Interspecific Variation ◽

Transgenerational Plasticity ◽

Monogonont Rotifers

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Gamete signalling underlies the evolution of mating types and their number

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2015.0531 ◽

2016 ◽

Vol 371 (1706) ◽

pp. 20150531 ◽

Cited By ~ 19

Author(s):

Zena Hadjivasiliou ◽

Andrew Pomiankowski

Keyword(s):

Mathematical Model ◽

Sexual Reproduction ◽

Mating Types ◽

Simple Mathematical Model ◽

Unicellular Eukaryotes ◽

Evolutionarily Stable

The gametes of unicellular eukaryotes are morphologically identical, but are nonetheless divided into distinct mating types. The number of mating types varies enormously and can reach several thousand, yet most species have only two. Why do morphologically identical gametes need to be differentiated into self-incompatible mating types, and why is two the most common number of mating types? In this work, we explore a neglected hypothesis that there is a need for asymmetric signalling interactions between mating partners. Our review shows that isogamous gametes always interact asymmetrically throughout sex and argue that this asymmetry is favoured because it enhances the efficiency of the mating process. We further develop a simple mathematical model that allows us to study the evolution of the number of mating types based on the strength of signalling interactions between gametes. Novel mating types have an advantage as they are compatible with all others and rarely meet their own type. But if existing mating types coevolve to have strong mutual interactions, this restricts the spread of novel types. Similarly, coevolution is likely to drive out less attractive mating types. These countervailing forces specify the number of mating types that are evolutionarily stable. This article is part of the themed issue ‘Weird sex: the underappreciated diversity of sexual reproduction’.

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A MATHEMATICAL MODEL FOR THE REPRODUCTION DYNAMICS OF TOXOPLASMA GONDII

Journal of Biological System ◽

10.1142/s0218339015400082 ◽

2015 ◽

Vol 23 (supp01) ◽

pp. S91-S100

Author(s):

JOHN ALEXANDER LEÓN MARÍN ◽

IRENE DUARTE GANDICA

Keyword(s):

Mathematical Model ◽

Partial Differential Equations ◽

Toxoplasma Gondii ◽

Epithelial Cells ◽

Sexual Reproduction ◽

Numerical Solution ◽

Definitive Host ◽

Initial Conditions ◽

Felis Catus ◽

One Dimensional

This paper presents a mathematical model describing the reproduction dynamics of the Toxoplasma gondii parasite in the definitive host Felis catus (cat). The dynamics is described by a system of partial differential equations defined in a one-dimensional region, with boundary and initial conditions. The model considers both asexual and sexual reproduction processes of the T. gondii parasite starting from the consumption of T. gondii oocysts from the environment, by the definitive host, and describing the reproduction dynamics until the cat expels infectious oocysts to the environment through its feces. The numerical solution of the system is obtained, and some simulations are made, leaving constant of transition and loss rates, since its variation does not produce significant changes in the reproduction, propagation and creation of new populations; and varying the initial consumption of oocysts from the environment by the cat. It is concluded that, either low or high, the involved populations are always reproduced; they spread by all over epithelial cells and subsequently are expelled to the environment through the cat feces. It is corroborated that the cats are potential multipliers of the oocysts and therefore, the main disseminators of the infection.

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