The first amphibians that lived on both land and water are ancestors of modern-day frogs and salamanders.
Invertebrates were formed and became active.
They evolved from original seed-eating features to forms with altered beaks for different diets.
Common ancestry.
Reptiles lay thick-shelled eggs that do not dry up in the sun, unlike those of amphibians.
Humerus, radius, ulna, carpals, metacarpals, and phalanges
Homo erectus probably ate meat.
Lichens do not grow in polluted areas, making them indicators of industrial pollution.
Antibiotic resistance in bacteria can be explained by Darwinian selection theory, where bacteria with mutations that confer resistance survive and reproduce, leading to a population that is increasingly resistant to antibiotics.
It proposes that all living organisms were created as they are today, that diversity has always been the same, and that the earth is about 4000 years old.
Excess use of these chemicals results in the selection of resistant varieties in a shorter time scale.
The two key concepts of Darwinian Theory of Evolution are branching descent and natural selection.
There have been extinctions of different life forms as well as the emergence of new forms of life.
Evolution is not a directed process; it is stochastic and based on chance events and mutations.
Agriculture came around 10,000 years back and human settlements started.
Louis Pasteur demonstrated through experimentation that life comes only from pre-existing life, disproving spontaneous generation.
Yes, human evolution can be considered a form of adaptive radiation as it involved the diversification of hominins adapting to different environments and lifestyles.
Hugo deVries introduced the idea of mutations causing evolution, which he termed saltation.
Darwin's finches
Amphibians evolved into reptiles.
The sum total of all the allelic frequencies is 1.
Common ancestry
Predators spotted white-winged moths against a contrasting dark background, leading to their decline, while dark-winged moths survived.
Convergent evolution refers to the phenomenon where different species evolve similar traits, such as placental mammals in Australia evolving into varieties that resemble corresponding marsupials, like the placental wolf and the Tasmanian wolf-marsupial.
A Coelacanth was caught in South Africa, which was thought to be extinct.
Vertebrate hearts or brains
The skull of a baby chimpanzee is more like the adult human skull than the adult chimpanzee skull.
Alfred Wallace, a naturalist who worked in the Malay Archipelago, came to similar conclusions about natural selection around the same time as Darwin.
A species is defined as a group of organisms that can interbreed and produce fertile offspring, sharing common characteristics and genetic makeup.
He concluded that existing living forms share similarities with each other and with life forms that existed millions of years ago.
Paleontological evidence refers to the study of fossils in different sedimentary layers, showing that life-forms varied over time and new forms arose at different times in Earth's history.
Pteridophytes.
It implies that life forms have changed over time through evolutionary processes.
An example of adaptive radiation is the diversification of Darwin's finches in the Galápagos Islands, where different species evolved to exploit various ecological niches.
About 20 feet.
The five factors are gene migration (gene flow), genetic drift, mutation, genetic recombination, and natural selection.
The founder effect occurs when a small group from a population migrates and establishes a new population, leading to changes in allele frequencies.
Natural selection is a process where heritable variations that enhance survival and reproduction become more common in a population.
Adaptive radiation
Genetic equilibrium refers to the condition where the gene pool (total genes and their alleles in a population) remains constant.
Evolutionary Biology is the study of the history of life forms on earth.
Around 350 million years ago.
Looking at stars represents peeping into the past, as the light we see has traveled millions of years to reach us.
Through selective breeding for agriculture, horticulture, sport, or security.
The modern-day descendants of reptiles include turtles, tortoises, and crocodiles.
The essence of Darwinian theory about evolution is natural selection, which suggests that organisms better adapted to their environment are more likely to survive and reproduce.
The first cellular forms of life arose slowly through evolutionary forces from non-living molecules.
It illustrates that those who can better adapt to their environment survive and increase in population size.
Fitness refers to the ability of an organism to survive and reproduce in a given environment, which is based on inherited characteristics that provide an advantage under specific conditions.
The Earth is estimated to be about 4.5 billion years old.
He observed a remarkable diversity, particularly noting small black birds known as Darwin's Finches.
Modern Homo sapiens arose during the ice age between 75,000-10,000 years ago.
'Panspermia' is the idea that life may have originated from spores transferred from outer space to Earth.
Natural resources are limited, populations are stable in size, members of a population vary in characteristics, and most variations are inherited.
One example of prehistoric cave art can be seen at Bhimbetka rock shelter in Raisen district of Madhya Pradesh.
Oparin and Haldane proposed that the first form of life could have come from pre-existing non-living organic molecules through chemical evolution.
S.L. Miller's experiment demonstrated the formation of amino acids under conditions simulating the early Earth atmosphere.
The conditions on early Earth included high temperatures, volcanic storms, and a reducing atmosphere containing methane and ammonia.
The first non-cellular forms of life, which could have originated 3 billion years ago, may have been giant molecules like RNA and proteins.
Whales, dolphins, seals, and sea cows.
Divergent evolution.
Convergent evolution.
Wings of butterflies and birds.
Plants were the first organisms to invade land.
Fish with stout and strong fins could move on land and return to water.
Industrialisation darkened tree trunks due to smoke and soot, favoring the survival of dark-winged moths over white-winged moths.
Relatively speaking, the earth is almost only a speck in the vast universe.
Fitness refers to the ability of an individual or population to survive and reproduce in a given environment, with those better fit leaving more progeny.
Evolution is described as a process.
The Neanderthal man had a brain size of 1400cc.
Fossils are remains of hard parts of life-forms found in rocks, indicating the existence of different life forms at various geological periods.
Components of human evolution include brain size and function, skeletal structure, and dietary preferences.
p represents the frequency of allele A and q represents the frequency of allele a.
All vertebrate embryos develop a row of vestigial gill slits just behind the head, which are functional only in fish.
Ichthyosaurs.
It represents the binomial expansion of (p + q)², indicating the expected frequencies of genotypes in a population.
Comparative anatomy shows similarities and differences among organisms of today and those that existed in the past, providing insights into evolutionary relationships.
Evidence for evolution includes comparative anatomy, fossil records, and comparative biochemistry, which demonstrate homology and the branching descent of species.
Chemical evolution is significant as it refers to the formation of biomolecules that preceded the appearance of the first cellular forms of life, laying the groundwork for biological evolution.
Pouched mammals.
Between 650-800cc.
The Hardy-Weinberg principle states that allele frequencies in a population are stable and constant from generation to generation.
Marsupials
Divergent evolution
To understand the changes in flora and fauna that have occurred over millions of years, we must understand the context of the origin of life, including the evolution of earth and the universe.
Whales, bats, cheetahs, and humans
The origin of life is considered a unique event in the vast history of the universe.
The proportion of dark-winged moths increased after industrialization.
Giraffes adapted by elongating their necks.
The rate of appearance of new forms is linked to the life cycle or lifespan of organisms; for example, microbes can multiply rapidly and evolve into new species within days, while fish or fowl may take millions of years due to their longer lifespans.
The Big Bang theory explains the origin of the universe through a singular huge explosion.
Evolution is treated as a consequence of the process called natural selection.
Homo sapiens arose in Africa.
The early atmosphere of Earth contained water vapor, methane, carbon dioxide, and ammonia.
Research and popular science articles suggest that some animals, such as certain primates and dolphins, exhibit signs of self-consciousness.
The frequency of AA individuals is calculated as p².
Karl Ernst von Baer disapproved Heckel's proposal, noting that embryos do not pass through the adult stages of other animals.
Darwin asserted that heritable variations that improve resource utilization will enable those individuals to reproduce and leave more progeny.
Climatic changes or evolution into birds.
Shrews.
Dryopithecus and Ramapithecus.
Around 900cc.
Mutations are random and directionless, while Darwinian variations are small and directional.
They were viviparous and kept them inside the mother’s body.
They were overridden by North American fauna.
Homo habilis.
The three outcomes are stabilisation, directional change, and disruption.
The first cellular forms of life appeared about 2000 million years ago.
Ethiopia and Tanzania.
Fossils of Homo erectus.
