Relationship between divergent evolution and homologous structures

Convergent evolution - Wikipedia

relationship between divergent evolution and homologous structures

Evidence for evolution: anatomy, molecular biology, biogeography, fossils, & direct observation. Some homologous structures can be seen only in embryos. (or amino acid differences in the proteins they encode) between two species, the more settings, but have distant relationships to ancestral species on mainlands. Difference Between Convergent and Divergent Evolution These kind have a Homologous structure (means structure are same, but functions. Two of these patterns are known as convergent and divergent evolution. The relationship between the analogous structures in different species that to the homologous structures seen in divergent evolution which have the same basic.

These are small-brained and relatively small-bodied, with a wet nose similar to that of a dog. The next big divergence occurred around 35 million years ago in the other phylogenetic branch of primates, the simians.

  • Divergent & Convergent Evolution: Definitions & Examples
  • Difference Between Convergent and Divergent Evolution
  • Evidence for evolution

This event resulted in the divergence of the common ancestor of all New World monkeys and Old World monkeys. It is speculated that the two groups underwent divergent evolution as a consequence of allopatric speciation. As the continents of America and Eurasia had by this point separated, the split could have been caused by a chance migration across the Atlantic Ocean. They evolved flat noses and prehensile tails, which act as a fifth limb and have the ability to grasp on to trees and branches.

These include familiar families such as capuchins and spider monkeys family: Cebidaemarmosets Callitrichidaeand howler monkeys Atelidae. The common ancestor of the Old World monkeys and apes split around 25 million years ago. Old World monkeys, or Catarrhini, are native to Africa and Asia, displaying a range of different adaptions to many types of habitat, from rainforests to savannah, mountains and shrubs.

There are both terrestrial and arboreal Catarrhini, many of which are familiar, such as macaques genus: Macacababoons Papio and langurs Semnopithecus. The apes, or Hominoidea, further diverged into two groups: Hylobatidaewhich are all native to Asia, and the great apes Hominidaewhich are native to Europe, Africa and Asia, and include orangutans genus: Pongogorillas Gorillachimpanzees Pan and humans Homo. It is important to remember that the modern primates we see today are not evolved from each other despite their similarities for example, great apes are not evolved from lesser apesbut that they are descended from a single common ancestor that formed two different species through divergent evolution.

Primate cladogram The Kit Fox and the Arctic Fox Two species that are very closely related and have undergone divergent evolution are the kit fox Vulpes macrotis and the Arctic fox Vulpes lagopus. The kit fox is native to Western North America, and is adapted to desert environments; it has sandy coloration, and large ears, which help it to remove excess body heat.

The Arctic fox is native to Arctic regions and lives in the Arctic tundra biome of the Northern Hemisphere.

Difference between Convergent and Divergent Evolution | Biology Dictionary

Best adapted to cold climates, it has thick fur, which is white in the winter and brown in the summer, and a small, round body shape that minimizes heat loss. Having diverged from a recent common ancestor, both these species have had to adapt to their extremely different habitats.

They have evolved into two species that are clearly very distinct in terms of their ears and coats, although they still retain the majority of their ancestral features. Related Biology Terms Convergent Evolution — The process whereby species that are not closely related, independently evolve functionally or visually similar structures. Parallel Evolution — The process in which related, but distinct, species independently evolve similar structures.

Divergent Evolution

Speciation — The process in which new and distinct species are formed. Natural Selection — The process in which species that are better adapted to their environment survive and reproduce, whereas those that are maladapted do not.

The structures present in the common ancestor of two species and that persist in their evolved lineage, albeit with a different form or function, are known as: Lemurs and humans are both primates.

Ancestral primates had brown eyes, as most primates do today.

relationship between divergent evolution and homologous structures

The genetic basis of blue eyes in humans has been studied in detail and much is known about it. It is not the case that one gene locus is responsible, say with brown dominant to blue eye colour. In lemurs, the differences between blue and brown eyes are not completely known, but the same gene locus is not involved. Carbon fixation While convergent evolution is often illustrated with animal examples, it has often occurred in plant evolution. For instance, C4 photosynthesisone of the three major carbon-fixing biochemical processes, has arisen independently up to 40 times.

These pomes incorporate five carpels and their accessory tissues forming the apple's core, surrounded by structures from outside the botanical fruit, the receptacle or hypanthium. Other edible fruits include other plant tissues; [49] for example, the fleshy part of a tomato is the walls of the pericarp. It is one of the most dramatic examples of convergent evolution in biology.

Difference between Convergent and Divergent Evolution

In three species studied, Cephalotus follicularisNepenthes alata and Sarracenia purpureathere has been convergence at the molecular level. Carnivorous plants secrete enzymes into the digestive fluid they produce. By studying phosphataseglycoside hydrolaseglucanaseRNAse and chitinase enzymes as well as a pathogenesis-related protein and a thaumatin -related protein, the authors found many convergent amino acid substitutions.

These changes were not at the enzymes' catalytic sites, but rather on the exposed surfaces of the proteins, where they might interact with other components of the cell or the digestive fluid. The authors also found that homologous genes in the non-carnivorous plant Arabidopsis thaliana tend to have their expression increased when the plant is stressed, leading the authors to suggest that stress-responsive proteins have often been co-opted [c] in the repeated evolution of carnivory.

The figure shows the number of inferred independent origins of C3-C4 photosynthesis and C4 photosynthesis in parentheses.

Phylogenetic reconstruction and ancestral state reconstruction proceed by assuming that evolution has occurred without convergence. Convergent patterns may, however, appear at higher levels in a phylogenetic reconstruction, and are sometimes explicitly sought by investigators.

The methods applied to infer convergent evolution depend on whether pattern-based or process-based convergence is expected. Pattern-based convergence is the broader term, for when two or more lineages independently evolve patterns of similar traits.

Process-based convergence is when the convergence is due to similar forces of natural selection.

relationship between divergent evolution and homologous structures

Stasis occurs when there is little evolutionary change among taxa. Frequency-based measures assess the number of lineages that have evolved in a particular trait space.