The "Cambrian explosion" is a term used to describe the abrupt appearance in the fossil record of major animal phyla, without intermediate forms in lower layers. This pattern of abrupt appearance can be observed for many groups of organisms, including crinoids (sea lilies).
The theory of evolution has pervaded most fields of knowledge. Therefore, it is important to know the fundamentals of this theory in order to understand how this ideology influences interpretations of data from nature and differs from the biblical creation model of the origin of life forms.
Cnidarians appear to have recruited as toxins the same kinds of proteins recruited by many other venomous animals. However, toxin diversity within groups of organisms does not appear to be related to the alleged evolutionary history of the various groups.
How can some people be so certain about evolution, while others, with the same certainty, deny it? Part of the answer can, in broad terms, be boiled down to the difference between what is seen and what is not seen. More specifically, and in the context of evolution itself, this disparity arises from the difference between microevolution and macroevolution. What are these two concepts, and how does the difference between them help explain much of the controversy surrounding the theory of evolution?
This article was published on the August 2019 issue of Signs of the Times.
In recent decades, epigenetics has been shown to be a promising field of research, since it describes changes in inheritance patterns that do not involve DNA modifications and are related to interactions between the organism and the environment. Epigenetic marks are chemical changes that occur in chromosomes and result in the silencing or activation of specific genes in different tissues. It has been…
A fossil bird recovered from Cretaceous lake deposits in China shows preservation of some soft tissues, including a pair of lungs that appear to have functioned in a way similar to those of living birds.