integrative phase of interactions among organisms with physiological expression and
genetic novelty (Apprill 2020; Carrapiço 2012; Munzi et al. 2019; Zook 2015). Three
years before the symbiosis concept, in 1875, the concept of mutualism was introduced
by the Belgian zoologist Pierre-Joseph Van Bénéden (1809–1894) and based on
Pierre-Joseph Proudhon’s (1809–1865) sociological ideas applied to the animal kingdom (Boucher 1985; Van Bénéden 1875). It was a significant step to understand the
importance of the relations between organisms (Boucher1985). This concept can be
defined as a beneficial relationship between different species of organisms present in
the association (Boucher 1985). Another important concept was symbiotismus, which
was introduced in 1877 by the German naturalist Albert Bernhard Frank (1839–1900)
in a work on lichens (Frank 1877). Symbiotismus and symbiosis are very similar
concepts in terms of biological definition, and although symbiosis was introduced one
year after symbiotismus, it is symbiosis the most well-known and used in biology
(Carrapiço 2015a).
To understand the importance of symbiosis and symbionts in biological science,
we must also go back to the introduction of the symbiogenesis concept in 1909 by
the Russian biologist Constantin Merezhkowsky (1855–1921). Working on symbiotic associations, namely lichens, Merezhkowsky developed the concept of
symbiogenesis as “the origin of organisms by the combination or by the association
of two or several beings which enter into symbiosis” (Carrapiço 2015a;
Merezhkowsky 1909; Sapp et al. 2002). He also presented in 1905 coherent scientific arguments showing that plastids arose from free-living cyanobacteria, showing
the importance of symbionts in evolution and in the complexification of organisms
and also in the origin of life under a symbiogenic perspective (Carrapiço 2015a;
Merezhkowsky 1905, 1909; Pereira et al. 2012). This work was further developed in
1920 in the article “La plante considerée comme un complexe symbiotique” (The
plant considered as a symbiotic complex) about the symbiotic origin of chloroplasts
and nucleus (Carrapiço 2015a; Merezhkowsky 1920). In opposition to contemporary
views of the time, Merezhkowsky defended that chloroplasts did not evolve from
mitochondria or protoplasm, but from free-living cyanobacteria, as he had presented
in 1905 (Carrapiço 2015a; Merezhkowsky 1920). These ideas point out, in some
way, the importance of the symbionts in the symbiotic process and their role in
biological evolution.
Another Russian botanist, Andrey Famintsyn (1835–1918), contemporary of
Merezhkowsky and also working on the symbiotic field, published in 1907 “On
the role of symbiosis in the evolution of organisms,”, where the author developed the
idea that symbiosis has an important evolutionary, or even adaptive, meaning.
Merezhkowsky, however, introduced a new classification of the living world using
for the first time associations between organisms to understand their biological
complexification and reinforce the importance of symbiosis, in particular the symbionts’ role as leading actors in the biological world structure and in the evolutive
process (Carrapiço 2015a; Merezhkowsky 1909; Sapp et al. 2002).
At the beginning of the twentieth century, Hermann Reinheimer, an almost
unknown English author born in Germany, published several books in the field of
symbiontology. Among them, three can be considered good examples of the author’s
598
F. Carrapiço
genetic novelty (Apprill 2020; Carrapiço 2012; Munzi et al. 2019; Zook 2015). Three
years before the symbiosis concept, in 1875, the concept of mutualism was introduced
by the Belgian zoologist Pierre-Joseph Van Bénéden (1809–1894) and based on
Pierre-Joseph Proudhon’s (1809–1865) sociological ideas applied to the animal kingdom (Boucher 1985; Van Bénéden 1875). It was a significant step to understand the
importance of the relations between organisms (Boucher1985). This concept can be
defined as a beneficial relationship between different species of organisms present in
the association (Boucher 1985). Another important concept was symbiotismus, which
was introduced in 1877 by the German naturalist Albert Bernhard Frank (1839–1900)
in a work on lichens (Frank 1877). Symbiotismus and symbiosis are very similar
concepts in terms of biological definition, and although symbiosis was introduced one
year after symbiotismus, it is symbiosis the most well-known and used in biology
(Carrapiço 2015a).
To understand the importance of symbiosis and symbionts in biological science,
we must also go back to the introduction of the symbiogenesis concept in 1909 by
the Russian biologist Constantin Merezhkowsky (1855–1921). Working on symbiotic associations, namely lichens, Merezhkowsky developed the concept of
symbiogenesis as “the origin of organisms by the combination or by the association
of two or several beings which enter into symbiosis” (Carrapiço 2015a;
Merezhkowsky 1909; Sapp et al. 2002). He also presented in 1905 coherent scientific arguments showing that plastids arose from free-living cyanobacteria, showing
the importance of symbionts in evolution and in the complexification of organisms
and also in the origin of life under a symbiogenic perspective (Carrapiço 2015a;
Merezhkowsky 1905, 1909; Pereira et al. 2012). This work was further developed in
1920 in the article “La plante considerée comme un complexe symbiotique” (The
plant considered as a symbiotic complex) about the symbiotic origin of chloroplasts
and nucleus (Carrapiço 2015a; Merezhkowsky 1920). In opposition to contemporary
views of the time, Merezhkowsky defended that chloroplasts did not evolve from
mitochondria or protoplasm, but from free-living cyanobacteria, as he had presented
in 1905 (Carrapiço 2015a; Merezhkowsky 1920). These ideas point out, in some
way, the importance of the symbionts in the symbiotic process and their role in
biological evolution.
Another Russian botanist, Andrey Famintsyn (1835–1918), contemporary of
Merezhkowsky and also working on the symbiotic field, published in 1907 “On
the role of symbiosis in the evolution of organisms,”, where the author developed the
idea that symbiosis has an important evolutionary, or even adaptive, meaning.
Merezhkowsky, however, introduced a new classification of the living world using
for the first time associations between organisms to understand their biological
complexification and reinforce the importance of symbiosis, in particular the symbionts’ role as leading actors in the biological world structure and in the evolutive
process (Carrapiço 2015a; Merezhkowsky 1909; Sapp et al. 2002).
At the beginning of the twentieth century, Hermann Reinheimer, an almost
unknown English author born in Germany, published several books in the field of
symbiontology. Among them, three can be considered good examples of the author’s
598
F. Carrapiço