also written von Haeckel, was an eminent German biologist, naturalist, philosopher, physician, professor and artist who discovered, described and named thousands of new species, mapped a genealogical tree relating all life forms, and coined many terms in biology, including anthropogeny, ecology, phylum, phylogeny, stem cell, and the kingdom Protista.

On the other hand, Michael K. Richardson, Professor of Evolutionary Developmental Zoology, Leiden University, while recognizing that some criticisms of the drawings are legitimate ( indeed, it was he and his co-workers who began the modern criticisms in 1998 ), has supported the drawings as teaching aids, and has said that " on a fundamental level, Haeckel was correct "

On the other hand, it does seem likely that Marr was influenced by Ernst Haeckel, a professor who popularized the notion of Social Darwinism among Germany's educated classes.

Lamarckism also appealed to those, like the philosopher Herbert Spencer and the German anatomist Ernst Haeckel, who saw evolution as an inherently progressive process.

Nevertheless, his chief interest was in human evolution, influenced by Ernst Haeckel, who reasoned that there must be intermediate species between apes and human.

Roux was a disciple of and influenced by Ernst Haeckel who believed the struggle for existence occurred at the cellular level.

Darwin was visited in October 1866 by the zoologist Ernst Haeckel, who over the years had built support for Darwin in Germany, now getting huge classes at Jena for his lectures on Darwinismus.

Haeckel promoted and popularized Charles Darwin's work in Germany and developed the controversial recapitulation theory (" ontogeny recapitulates phylogeny ") claiming that an individual organism's biological development, or ontogeny, parallels and summarizes its species ' evolutionary development, or phylogeny.

Ernst Haeckel attempted to synthesize the ideas of Lamarckism and Goethe's Naturphilosophie with Charles Darwin's concepts.

While often seen as rejecting Darwin's theory of branching evolution for a more linear Lamarckian " biogenic law " of progressive evolution, this is not accurate: Haeckel used the Lamarckian picture to describe the ontogenic and phylogenic history of the individual species, but agreed with Darwin about the branching nature of all species from one, or a few, original ancestors.

Haeckel showed a main trunk leading to mankind with minor branches to various animals, unlike Darwin's branching evolutionary tree.

Ernst Haeckel was particularly ardent, aiming to synthesise Darwin's ideas with those of Lamarck and Goethe while still reflecting the spirit of Naturphilosophie.

Historians write that most such political and economic commentators had only a superficial understanding of Darwin's scientific theory, and were as strongly influenced by other concepts about social progress and evolution, such as the Lamarckian ideas of Spencer and Haeckel, as they were by Darwin's work.

Ernst Haeckel ( 1866 ), in his endeavour to produce a synthesis of Darwin's theory with Lamarckism and Naturphilosophie, proposed that " ontogeny recapitulates phylogeny ," that is, the development of the embryo of every species ( ontogeny ) fully repeats the evolutionary development of that species ( phylogeny ), in Geoffroy's linear model rather than Darwin's idea of branching evolution.

In the latter 19th century, the department of zoology taught evolutionary theory, with Carl Gegenbaur, Ernst Haeckel and others publishing detailed theories at the time of Darwin's " Origin of Species " ( 1858 ).

As a professor of anatomy at the University of Jena ( 1855 – 1873 ) and at the University of Heidelberg ( 1873 – 1903 ), Carl Gegenbaur was a strong supporter of Charles Darwin's theory of organic evolution, having taught and worked, beginning in 1858, with Ernst Haeckel, 8 years his junior.

His ideas changed in summer 1862 when he returned to study at Jena, where Ernst Haeckel introduced him to Darwin's work and theories.

In contrast to most of Darwin's supporters, Ernst Haeckel put forward a doctrine of evolutionary polygenism based on the ideas of the linguist and polygenist August Schleicher, in which several different language groups had arisen separately from speechless prehuman Urmenschen, which themselves had evolved from simian ancestors.

In addressing his embryo drawings to a general audience, Haeckel does not cite any sources, which gives his opponents the freedom to make assumptions regarding the originality of his work.

Although Haeckel stressed comparative embryology and Gegenbaur promoted the comparison of adult structures, both believed that the two methods could work in conjunction to produce the goal of evolutionary morphology.

The terms " gastrula " and " gastrulation " were coined by Ernst Haeckel, in his 1872 work " Biology of Calcareous Sponges ".

In Phylum, Rockman draws upon the work of Ernst Haeckel, a proponent of Darwinism.

During these times, he worked several times at facilities located by the sea: Heligoland alongside Haeckel in 1865, Hamburg in 1866, Millport, Scotland with David Robertson in 1867 and 1868 and moved to Messina, Italy, during the winter of 1868 together with his friend and colleague Nicholas Miklouho-Maclay to work on the marine life of the Straits of Messina.

Darwin told Haeckel " I doubt whether my strength will last for much more serious work.

The word " ecology " (" Ökologie ") was coined in 1866 by the German scientist Ernst Haeckel ( 1834 – 1919 ).

The term " ecology " () is of a more recent origin and was first coined by the German biologist Ernst Haeckel in his book Generelle Morphologie der Organismen ( 1866 ).

< div style =" border: none ; width: 180px ;">< div class =" thumbcaption "> Ernst Haeckel ( left ) and Eugenius Warming ( right ), two founders of ecology </ div ></ div ></ div >

This contention may look convincing at first glance inasmuch as On the Origin of Species is full of observations and proposed mechanisms that clearly fit within the boundaries of modern ecology ( e. g. the cat-to-clover chain – an ecological cascade ) and because the term ecology was coined in 1866 by a strong proponent of Darwinism, Ernst Haeckel.

Nevertheless, Bischoff ’ s main argument was in reference to Haeckel ’ s drawings of human embryos, for Haeckel is later accused of miscopying the dog embryo from him.

German naturalist Ernst Haeckel proposed a monistic pantheism in which the idea of God is identical with that of nature or substance.

In the 19th century, Haeckel developed a materialist form of hylozoism, specially against Rudolf Virchow's and Hermann von Helmholtz's mechanical views of humans and nature.

In his Die Welträtsel of 1899 ( The Riddle of the Universe 1901 ), Haeckel upheld a unity of organic and inorganic nature and derived all actions of both types of matter from natural causes and laws.

Haeckel advanced a version of the earlier " recapitulation theory ", previously set out by Étienne Serres in the 1820s and supported by followers of Geoffroy including Robert Edmond Grant, which proposed a link between ontogeny ( development of form ) and phylogeny ( evolutionary descent ), summed up by Haeckel in the phrase " ontogeny recapitulates phylogeny ".

Haeckel introduced the concept of " heterochrony ", which is the change in timing of embryonic development over the course of evolution.

Haeckel ’ s illustrations show vertebrate embryos at different stages of development, which exhibit embryonic resemblance as support for evolution, recapitulation as evidence of the Biogenetic Law, and phenotypic divergence as evidence of von Baer ’ s laws.

Haeckel ’ s embryo drawings are primarily intended to express his idiosyncratic theory of embryonic development, the Biogenetic Law, which in turn assumes ( but is not crucial to ) the evolutionary concept of common descent.

Haeckel portrays a concrete demonstration of his Biogenetic Law through his ‘ Gastrea ’ theory, in which he argues that the early cup-shaped gastrula stage of development is a universal feature of multi-celled animals.

Haeckel then provided a means of pursuing this aim with his biogenetic law, in which he proposed to compare an individual's various stages of development with its ancestral line.

Haeckel used embryology extensively in his recapitulation theory, which embodied a progressive, almost linear model of evolution.

Ernst Haeckel ( 1834 – 1919 ) became famous for his " recapitulation theory ", according to which each individual mirrors the evolution of the whole species during his life.

Early twentieth-century biologists like Ernst Haeckel viewed embryology as a recapitulation of evolution, which implies a kind of organising memory, and a few modern biologists, such as Rupert Sheldrake, influenced by Jungian ideas and by vitalism, have posited organising fields of life consisting of memories and drives.

Yet, in our times, scientific hylozoism – whether modified, or keeping the trend to make all beings conform to some uniform pattern, to which the concept was adhered in modernity by Herbert Spencer, Hermann Lotze, and Ernst Heinrich Haeckel – was often called upon as a protest against a mechanicistic view of the world.

In what was to be the last decade of his life, he penned works such as Parsifal Unveiled, which details the esoteric symbolism of the Wagner opera, and Gnostic Anthropology in which he heavily criticizes the theories of Darwin, Haeckel, " and their followers ".

Haeckel later abandoned this idea which is revived by Hadzi in 1953.

Haeckel divided human beings into ten races, of which the Caucasian was the highest and the primitives were doomed to extinction.

Ernst Haeckel claimed that Negroes have stronger and more freely movable toes than any other race which is evidence that Negroes are connected to apes because when apes stop climbing in trees they hold on to the trees with their toes, Haeckel compared Negroes to “ four-handed ” apes.

Ehret was a proponent of the emerging back-to-nature renaissance in Germany and Switzerland during the latter part of the 19th century, which was inspired by writers such as Meister Eckhart, Christoph Wilhelm Hufeland, Nietzche, Goethe, Herman Hesse, Ernst Haeckel and Eduard Baltzer as well as the healing traditions of Roman and Greek philosophers such as Paracelsus, Empedocles, Seneca, Plutarch, Porphyry, Galen, Hippocrates, Socrates, Pythagoras, Plato and Aristotle.

In modern biology ( e. g. Haeckel and Fritz Müller ), palingenesis has been used for the exact reproduction of ancestral features by inheritance, as opposed to kenogenesis, in which the inherited characteristics are modified by environment.