When a living organism reproduces, genes are passed from one generation to the next, thus producing inherited traits in a species. Evolution is a gradual process of changing in the genetic material of a population of organisms from one generation to the next. Most changes are extremely gradual, but can accumulate over time and can cause substantial biological changes to organisms.
Many feel evolution runs on the basis of natural selection, which is a process that causes helpful genetic traits to become more common in a breeding population. The process of evolution helps insure the survival of all species of life. Charles Darwin was an English naturalist who developed the theory of natural selection and presented compelling evidence that all organisms have evolved over time from common ancestors.
Darwin’s research has significantly impacted the scientific community and changed the way people view many theories of life. Here is a list of the Top 10 recent signs and evidence that evolution is a factual scientific explanation. You may also be interested in reading our top 10 list of arguments that can’t be won where evolution or creation was at the top of the list.
10. Stickleback Fish
The stickleback fish is part of the Gasterosteidae family and can be found in freshwater environments in Europe, Asia, and North America. Sticklebacks have no scales, but are protected by bony armor plates. These creatures have intrigued marine biologists for years, as many populations of the fish have evolved with genetic changes and displayed major adaptations in their bony armor styles. This evolutionary shift occurs when there is an increasing in the frequency of a rare genetic variant in a single gene of the creature.
These fish helped scientists discover that changes in a single gene can produce a major difference in the selector armor and body style of wild fish. It identified a specific genetic mechanism that controls a dramatic change in skeletal patterns. This finding has many implications towards the process of genetic evolution of organic species. It will help us eventually discover exactly how new animal types evolve in nature. The research is suggesting that evolution can occur quickly and only a few minor genetic changes can allow a migrating species to adapt and populate different environments.
9. Darwin’s Tubercle
Darwin’s Tubercle is a congenital ear condition which presents a thickening of the upper and middle thirds of the human ear. The feature can be seen in numerous primates and the phenomenon was used by Charles Darwin to support research indicating a common ancestry between primates. Today, the feature is present in approximately 10.4% of the population and very few newborns. The feature is thought to help animals control and regulate sound. As intelligence of the human species evolved at a rapid pace various visual and auditory organs were no longer needed and gradually removed themselves from our anatomy.
Humans are also born with a third-eyelid that is useless and very small. It is represented in a small membrane that is visible in the human eye and used to function as a protective shield.
Many people believe that the coccyx or tailbone is proof of what was a human tail. Darwin’s discoveries surrounding the tubercle were extremely important in developing the facts surrounding the theory of evolution.
8. Toxic Australian Toads
The toad problem in Australia is really bad. In 1935, Cane toads were brought to Australia from Hawaii to control the spread of beetles that were killing the sugar cane crop. It might have been a short term solution, but the lasting problem is horrendous. The toads have quickly expanded their range to cover more than a third of Australia’s total land area. They are spreading at a rate of 30 miles per year. A deadly chemical defense system has been devised to kill the pests, which is not good for crops and ground water.
Experimentation on the toads discovered that the creatures that were leading the land expansion had legs that were 6% larger then others. A study was conducted that showed that newer populations of toads tended to have longer legs than older established species. This gives the toad an ability to jump higher, move faster, and cover more ground on a daily basis. The grave mistake to introduce toads to this environment is a problem that is getting worse every day. The toad species is evolving to its surroundings and gaining more defenses, which is not good for Australia’s economy.
7. Humans Influence Natural Selection
Many studies have been conducted that show that the mass technological growth of the human race is greatly affecting other organisms. Many species have to adjust to human expansion and mass transportation systems. One clear example is the bee crisis that many areas of the world are facing. Humans have interfered with the genetics of many bee populations and helped in transporting different species all over the world. This has helped cause the spread of the tiny parasite Varroa Destructor.
Varroa Destructor feeds off the bodily fluids of bees creating a deadly virus that is demolishing populations. There has been a mass expansion of bee populations since airplanes, trains, and cars became commercially produced. In the past, one of human’s biggest faults was using various poisons and strategems to try and fix this evolutionary problem, but this will only cause more abnormalities in the food chain.
Many correlational studies have shown that trophy game, such as big fish and caribou are reproducing at a younger age and becoming smaller in size. Many hypothesize that this is to counter-act the hunting and fishing of many human populations, who prefer to hunt large game. Many species are also being affected by the national problem of global warming.
6. Hypolimnas Bolina
The Great Eggfly, also called the Blue Moon Butterfly, is a species of nymphalid butterfly that is found in many areas of the world including Madacascar, Southeast Asia, Australia, Japan, and New Zealand. It is a black bodied butterfly with an average wing span of 7–8½ cm. The butterfly can be found in wooded country, forests, thick and moist scrub, and the greener parts of the uninhabited terrain.
In the last ten years scientists have come to realize that a parasite was killing all of the male members of hypolimnas bolina on the Samoan islands of Upolu and Savaii. The pest would infect the females and then kill the males before they were hatched. The problem was so severe that in 2001 males inhabited only 1% of the population and the species was on the verge of extinction in this area of the world.
In the span of one year and 10 generations in the hypolimnas bolina family, the male butterfly’s evolved and obtained a suppressor gene that prevented the killer bacteria from spreading. In modern days the male population has increased to 40% in the colonies on these islands. Evolution is often much more evident in insects, as a family generation and lifespan is much shorter then with primates.
5. Brown Anole Lizard
Anolis sagrei is a lizard species native to Cuba and the Bahamas. They were also introduced in many areas of the United States, including Georgia, Texas, and Hawaii. In a famous experimental study, a research group led by Jonathan Losos of Harvard University discovered that when a brown anole population was introduced to a new predator, natural selection occurred in a six month period of time.
The goal of the study was to prove the hypothesis that evolution was not a prolonged occurrence. The scientists studied twelve different islands and introduced the predatory lizard to six, using the other six islands as a comparative sample. After six months, surveys found that anole populations dropped by 50% on the islands with the new predatory lizards.
The anole survivors had longer legs then the species previously inhabiting the islands. In the next six months of study another genetic change was recorded and the legs of the anole lizard species began to become short and stubby, as they were spending more of their time in trees. Female species were also recorded as becoming larger in size, ultimately making them harder for smaller animals to digest.
4. Darwin’s Finches
The second voyage of the HMS Beagle occurred December 1831 to October 1836 and the mission of the voyage was to conduct hydrographic surveys around the coasts of the southern part of South America. A young Charles Darwin was the expert geologist on this voyage. Darwin spent most of his time exploring the land and exhausted only 18 months at sea. He spent time researching on the Galápagos Islands, studying the vast number of endemic species. Darwin had incredible observational skills and noticed that there were numerous different finch species on the island. One species of the birds would grow slightly larger wings and have curved beaks in relation to the geographic location on the island.
Darwin recognized and recorded 14 separate combinatory species of Passerine birds in the area. The various niches of finches on the Galápagos Island are constantly evolving every year. The evolution of these birds can be readily studied and recorded. The medium ground finch that lives in this area recently downsized its beak, so that it could get small seeds more efficiently, after a larger finch species arrived on the island and began competing for food. Many scientists travel to this area because the experimental conditions are untouched and natural changes occur at an alarmingly fast rate.
3. Bacterial Evolution
Natural selection is most evident in life forms that have extremely rapid life cycles, such as bacteria. Bacteria can reproduce and span an entire generation in only a few short weeks. Many types of bacteria are helpful to human and animal health, but others cause infectious diseases. The quick evolution of disease-causing bacteria has been well documented and involves some of the most important medical research in the world.
A person who becomes ill can be given antibiotic drugs, which destroys the deadly bacteria in the human body, but not all of the bacteria get removed. The remaining bacteria that have already been contaminated by the antibiotic will become resistant to the drug in a short amount of time. If these certain bacteria reproduce then the disease will evolve to resist the medicines that we have developed. This is why antibiotics are becoming stronger and stronger, which is why medical researchers are always trying to develop more effective future medicines. As long as harmful bacteria and disease exist, evolution will be a formidable opponent against cures and medicine.
2. Land Living Ancestors of Whales
The giants of the sea have an extremely interesting story of origin. Whales are marine mammals of order Cetacea and have been left seriously endangered in many areas of the world. All cetaceans, including whales, dolphins and porpoises are the evolutionary decedents of land-living animals of the Artiodactyl order or even-toed ungulates. Today, certain cetaceans and artiodactyl are organized under the super-order Cetartiodactyla.
The term Cetartiodactyla is used to describe the classification that whales have evolved from within the artiodactyls. The hippopotamus is widely considered to be the closest land relative of the whale. Scientists and historians have estimated that whales entered the world’s oceans roughly 50 million years ago. Humans are just beginning to understand the complex behavior and characteristics of whales.
It is interesting that a species so large could evolve from land to sea. Cetaceans are the smartest creatures in the sea and this intelligence can be traced back to their modern land living ancestors. I wonder what geological phenomenon could have caused this mass population of animals to enter earth’s seas.
1. Evolution of Modern Man
As an organism evolves certain aspects of the anatomy become not as necessary and on occasion useless. This can be influenced by a new habitat, natural disaster, or even adaptation to disease prevention. When this occurs an organ that at one point in ancient history was essential for survival has become less important to the species. This is a sign of evolution and can clearly be seen in the human body.
Humans get goose bumps when they are cold, frightened, angry, or in awe of something. Before clothing goose bumps were an important way for humans to appear larger and more dangerous to prey. Today goose bumps have shrunk to an almost unnoticeable size. Humans also have an extra ear muscle, wisdom teeth, the appendix, and the Jacobson’s organ. The Jacobson’s organ is located in the nose of many animals. It is a smell organ which detects pheromones and can trigger sexual desire, alarm, and food sense. Humans are born with the organ, but early in development it shrinks and becomes useless. The plantaris muscle is used by many animals for gripping and manipulating objects with their feet. Humans are born with this muscle, but it is so underdeveloped that it is often taken out by doctors to reconstruct other areas of the body. Approximately 9% of the human population is born without the plantaris muscle.
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