Evolutionary trends are either progressive or retrogressive. During progressive evolution new structures are created whereas in retrogressive evolution the existing structures are reduced or eliminated.
Adaptation for stronger shells.
Perhaps the most significant evolutionary trend among the metazoan invertebrate phyla is that of cephalization. This term refers to the development of a head, containing a brain. Another process called segmentation allowed animals to develop distinct body parts, such as legs, wings and feelers.
evolutionary changes in organisms
Evolutionary theory provides a framework for understanding the relationships between organisms based on their shared ancestry and descent with modification. This has greatly influenced taxonomy by allowing classifications to reflect the evolutionary history of organisms, leading to more accurate and robust classification systems. By incorporating evolutionary principles, taxonomists can better organize and categorize species based on their evolutionary relationships.
DNA is often studied to find out about evolutionary relationships. By comparing the similarities and differences in the genetic material (DNA sequences) of different species, scientists can infer their evolutionary relationships and construct evolutionary trees. This field of study is known as molecular phylogenetics.
macroevolution .........novanet
Adaptation for stronger shells.
Direct Development vs Indirect Development.
Secular trends in new childhood epidemics, insights from evolutionary medicine.
Air-breathing animals do not return to breathing water.
macroevolution .........novanet
Misidentification of Cope's Rule - Functional or Physical Boundaries - Signor-Lipps Effect
a natural system of classification is that system of classification in which the organism is classified on the basis of their vegitative characters which are permanent and do not change with the envoirment this system of classification avoids the grouping of hetereogeneous and un related groups of organisms according to this sytem plants are classified on the basis of evolutionary trends while as animals are classified on basis of both evolutionary and phylogenetic trends........junaid
a natural system of classification is that system of classification in which the organism is classified on the basis of their vegitative characters which are permanent and do not change with the envoirment this system of classification avoids the grouping of hetereogeneous and un related groups of organisms according to this sytem plants are classified on the basis of evolutionary trends while as animals are classified on basis of both evolutionary and phylogenetic trends........junaid
a natural system of classification is that system of classification in which the organism is classified on the basis of their vegitative characters which are permanent and do not change with the envoirment this system of classification avoids the grouping of hetereogeneous and un related groups of organisms according to this sytem plants are classified on the basis of evolutionary trends while as animals are classified on basis of both evolutionary and phylogenetic trends........junaid
Observing trends in physical characteristics and grouping them in a way that demonstrates gradual change.
Benthic snail larvae are more likely to become isolated and therefore speciate at a higher rate creating more lineages.