Recapitulation Reference library
Encyclopedia of Evolution
...of von Baer and to the notion of divergence in the embryonic history. Then, in 1859 and following his reading of T. H. Huxley's translation of von Baer, Darwin also noted the importance of studying development for evidence of the animal's ancestral characteristics. After all, the divergence von Baer had discussed was remarkably similar to the descent by modification that Charles, Darwin envisioned. Darwin's epochal book On the Origin of Species appeared in 1859 . In it, Darwin carefully developed his new interpretation of animal life, emphasizing...
evergreen Quick reference
A Dictionary of Ecology (5 ed.)
...Applied to a tree or shrub that has persistent leaves, and whose crown is never wholly bare. Although the entire plant remains green throughout the year, each leaf has a limited life span, but is physically tougher and usually longer-lived than a deciduous leaf. Evergreen leaves have the advantage that where nutrients such as nitrogen are in short supply their longer life span allows a more efficient use of the limited...
Development Reference library
Encyclopedia of Evolution
...ideas for his evolutionary theories from von Baer. These included (1) a branching versus linear form of descent, (2) the idea that similar structures reveal common descent, and (3) the idea of using embryonic forms in classification. Because differences in adult form arise during development, von Baer's laws also led Darwin to see that the predictable similarities between the embryonic forms of different groups of organisms were strong support for his theory of evolution. Together, the ideas of von Baer, Schleiden and Schwann, and Darwin formed the...
History of Evolutionary Thought Reference library
Encyclopedia of Evolution
...embryologist Karl Ernst von Baer ( 1792–1876 ), the naturalist Louis Agassiz ( 1807–1873 ), and the poet Goethe ( 1749–1832 ), science consisted in extracting general forms from the variety of patterns that are discernible in nature. For each natural group, an archetype exists, and the goal of science is to discover these archetypes. Just as there is the ideal fish, ideal vertebrate, and ideal plant, there is the ideal mineral. Each of these archetypes can be discovered by stripping away all accidental features to lay bare the essence of the thing....
Epigenesis and Preformationism Reference library
Encyclopedia of Evolution
...the problems. Microscopists could duplicate the work of one another, demonstrate their observations to others, and replicate their own work. Furthermore, the new instruments had much greater magnification and resolution. Thus, when the Prussian naturalist Karl Ernst von Baer published his monumental work on animal generation in 1828 , he was able to demonstrate with great microscopical acuity that the developing embryo emerged gradually from undifferentiated material in the female ovum. This work was continued by both Theodor Schwann and Matthias...
Amphibians Reference library
Encyclopedia of Evolution
...Frogs have a dazzling array of evolutionary novelties associated with reproduction. Their diverse vocal signals of the males are used for mate advertisement and territorial displays. Parental care is highly developed in many lineages, including brooding of developing larvae on a bare back, in pouches on the back of females, in the vocal sacs of males, and in the stomach of females. Some females in some unrelated lineages of hylids and dendrobatids raise their tadpoles in the watery confines of a bromeliad axil and supply their own unfertilized eggs as food....
Karl Ernst von Baer
Meleagrididae
Meliphagidae
Cracidae
Musophagidae
Philepittidae
cere
wattle
New World Vultures
biogenetic law
recapitulation of phylogeny
fugitive species
hollow phase
