Answer: Decay
According to Decay theory, when we learn something new, a neurochemical memory trace forms, but over time this trace disintegrate
Fill In the Blank Question
The enzyme to which cyclin binds during interphase and mitosis, triggering and controlling activities during the cell cycle is called _____ ______
The activities of the s phase are maintained by signaling pathways functioning with the cyclase kinases isoenzyme (Cdks)
Throughout the cell election's metaphase and mitosis-initiating events, whichever having valid to cyclin?The main protein kinase that triggers regular mitosis in cells is cyclin-dependent cdk 1 (CDK1). When CDK1 binds to B-type cyclins, primarily cyclin B1, it becomes activated and phosphorylates substrates necessary for mitotic entry.
What regulates the Cyclin-Dependent Kinases' ability to function as enzymes?Without the appropriate cyclin subunit, the CDK enzyme is 40,000 times less active than it is in the quel heterodimer complex, making it crucial for functional response. The CDK activity is controlled by their connection with partner components known as cyclins.
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Identical twins are produced when a fertilised egg cell divides in two. Explain why identical twins share many, but not all, of their characteristics????
Answer:
Because Some identical twins are not both Male and male /Female and Male
In a study, 82% of head lice were found to be resistant to substances used to treat head lice infestations. Use your knowledge of natural selection to explain how this has happened??????
Answer:
The phenomenon of head lice becoming resistant to the substances used to treat them is an example of natural selection in action.
Initially, when a new substance is used to treat head lice infestations, the majority of the lice population may be susceptible to it. However, some individual lice may have a genetic variation that makes them resistant to the substance. These lice survive and reproduce, passing on their resistant genes to their offspring.
Over time, as the susceptible lice die off and the resistant lice continue to reproduce, the overall lice population becomes more resistant to the substance. This is because the resistant genes are now more common in the population.
This process is known as natural selection. In this case, the substance used to treat head lice infestations is acting as a selective pressure, favoring the survival and reproduction of lice with the resistant genes. As a result, the resistant genes become more common in the population over time.
This is why, in the study mentioned, 82% of head lice were found to be resistant to the substances used to treat them. The resistant genes have become prevalent in the head lice population due to the selective pressure of the treatments used.
Describe environmental variation in intertidal zones.
the intertidal zone is such an extermely variable environment because it environment experience very high change in elements of the environment it is also called littoral zone it also have rock and Sandy Beaches
Some of the micro-organism are not single cells how are they arranged?
Answer:
Some microorganisms are not single cells, and they can be arranged in different ways. For example, some microorganisms form clusters or colonies, while others form long filaments or chains. Some microorganisms, such as certain types of algae, form multicellular structures that resemble higher plants. Additionally, some bacteria can form structures called biofilms, which are communities of cells that are attached to a surface and encased in a protective matrix. The arrangement of microorganisms can vary depending on their species, environment, and other factors.
Explanation:
During the summer of 1988, fires burned sections of the Everglades, leaving a patchwork of burned and unburned areas. In the year following the fires, wildflowers sprouted in all the burned areas, closely followed in subsequent years by seedlings of the trees that normally grow in the area. What changes in the ecosystem will take place during secondary succession
The changes that will take place in ecosystem during the course of succession is the flowers will eventually be shaded out by the trees and will not be able to grow. Option B.
An ecosystem is a structural and functional unit of ecology in which living species interact with one another and with their surroundings. An ecosystem, in other terms, is a series of interactions between creatures and their surroundings. A.G. Tansley, an English botanist, created the word "ecosystem" in 1935.
The Yellowstone fires of 1988 were the biggest wildfire in the history of Yellowstone National Park in the United States. Due to dry conditions and increased winds, the flames swiftly expanded out of control, uniting into numerous enormous conflagrations that lasted for several months. The flames almost damaged two main visitor locations, and the park was closed to all non-emergency workers for the first time in its history on September 8, 1988.
Only the coming of cold, damp weather in late fall put a stop to the flames. With various levels of intensity, 793,880 acres (3,213 km2), or 36% of the park, burnt.
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Complete question:
During the summer of 1988, fires burned much of Yellowstone National Park, leaving a patchwork of burned and unburned areas. In the year following the fires, wildflowers sprouted in all the burned areas, closely followed in subsequent years by seedlings of the trees that normally grow in the area, such as aspens and lodgepole pines. What changes in the ecosystem will take place during the course of succession?
answer choices
A. The flowers will shade out the small trees creating a permanent meadow.
B. The flowers will eventually be shaded out by the trees and will not be able to grow.
C. The trees will not grow well because of the toxic chemicals produced by the flowers.
D. The trees will take the nutrients that the flowers need, and the flowers will be stunted
2. Using the results of his experiments with pea plant
crosses, what did Gregor Mendel discover?
A) the principles of dominance, segregation, and
independent assortment
B) that pea plants develop mutations after expos
to radiation
C) intermediate inheritance and gene linkage
D) that DNA is involved in the inheritance of
dominant traits
ubati
Using the results of his experiments with pea plant crosses, Gregor Mendel discovered: A) the principles of dominance, segregation, and independent assortment.
What was the pea plant crosses experiment?In this famous experiment, Mendel cross- pollinated pea plants based on their different features to make important discoveries on how traits are inherited between the generations.
Mendel crossed the pure lines of pea plants. Dominant traits, like purple flower color, appeared in first-generation hybrids (F1), whereas recessive traits, like white flower color were masked. But recessive traits reappeared in second-generation (F2) pea plants in ratio of 3:1 (dominant to recessive).
The experiment allowed Mendel to conclude on two laws of Inheritance; that are Law of Segregation and Law of Independent Assortment.
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Why is Saturn considered to be an outer planet?
It is located after the main asteroid belt.
It is located between the sun and the main asteroid belt.
It is the closest planet to the main asteroid belt.
It is the farthest planet away from the sun.
Answer: It is the farthest planet away from the sun.
Explanation:
Saturn is the sixth planet away from the sun so it's consider a outer planet.
In one paragraph, explain how matter such as water, nitrogen, oxygen, and carbon dioxide cycles in an ecosystem.
Energy changes forms as it moves through an ecosystem, but no new energy is produced. As a result, energy and matter are preserved throughout all ecosystem processes.
How do the ecosystem cycles water carbon and nitrogen impact life within the ecosystem?The three main cycles of an ecosystem are the water cycle, the carbon cycle and the nitrogen cycle. When these three cycles are in harmony, they remove waste from the ecosystem and replenish it with the nutrients it needs to support life.
What is an ecosystem's cycle of matter?As these organisms live and die, matter circulates between the air and soil, as well as among plants, animals, and microbes. In addition to absorbing gases and water from the environment, organisms also emit waste materials back into it.
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arrange the different phases in the correct order. write down only the correct letter and no phase can be repeated:based on meiosis.
The different phases in the correct order:
Correct order: A B C D E F G H I
What is meiosis?Meiosis is a type of cell division that occurs in sexually reproducing organisms to produce gametes (eggs and sperm). It involves two rounds of cell division, resulting in four daughter cells with half the number of chromosomes as the parent cell. Meiosis is important for maintaining the correct number of chromosomes in a species, as well as creating genetic diversity by mixing up the genetic information from the parents. It is a complex process that involves a series of phases including prophase I, metaphase I, anaphase I, telophase I, and then prophase II, metaphase II, anaphase II, and telophase II. During meiosis, homologous chromosomes pair up and exchange genetic information through a process called recombination, and then separate during the first division. The second division separates the sister chromatids, resulting in four haploid cells that are genetically distinct from each other and from the parent cell.
Here,
A. Interphase
B. Prophase I
C. Metaphase I
D. Anaphase I
E. Telophase I
F. Prophase II
G. Metaphase II
H. Anaphase II
I. Telophase II
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What is true of the population shown in this graph?
Responses
There are no limiting factors to control population growth.
It shows the effect of overpopulation on a species.
The number of individuals will eventually drop to zero.
The population has increased until it has reached its carrying capacity.
The population has increased until it has reached its carrying capacity is true of the population.
Option D is correct.
Does a population's expansion be controlled by a limiting factor?Anything that slows or prevents a population from expanding is a limiting factor. Bites, such as food, partners, and competition with other organisms for resources, are examples of limiting factors.
What causes limiting factors?Limiting factors include food, water, light, space, shelter, and access to companions. Individuals will die of starvation, desiccation, and stress in an organism, group, or population that lacks sufficient resources to sustain it, or they will not bear children.
Incomplete question :
What is true of the population shown in this graph? Responses
A.There are no limiting factors to control population growth.
B.It shows the effect of overpopulation on a species.
C.The number of individuals will eventually drop to zero.
D.The population has increased until it has reached its carrying capacity.
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D: The population has increased until it has reached its carrying capacity.
Explanation: k12 1.05
Which of the following is an example of the bottleneck effect?
A
Bald eagles are hunted until near extinction, then the population recovers.
B
A small group of iguanas float to an island, and a new population is started.
C
Red fox pups are more likely to survive in a snowy environment if they are born white.
D
A farmer chooses seeds from the largest apples to plant next year, which results in larger apples from year to year.
Answer:
The correct answer is A.
The bottleneck effect refers to a reduction in population size, often caused by a random event such as a natural disaster or human activity, that leads to a loss of genetic diversity in the population. In this case, the population of bald eagles is reduced to near extinction, which would likely result in a significant loss of genetic diversity. If the population recovers, it may do so with reduced genetic variation, which can have negative consequences for the species in the long term.
B is an example of the founder effect, which occurs when a small group of individuals colonizes a new area and starts a new population. The genetic diversity of the new population may be influenced by the characteristics of the founding group.
C is an example of natural selection, where traits that confer an advantage in a particular environment are more likely to be passed on to future generations.
D is an example of artificial selection, where humans intentionally select certain traits to be passed on to future generations. This can result in changes in the genetic makeup of a population over time, but it is not an example of the bottleneck effect.
TRUE OR FALSE if you were examining a plasmodesma under a microscope, you would expect to find a plant cell at each end
Answer:
true
Explanation:
Is this the right order of water cycle?
Precipitation, interception, runoff, collection, infiltration, percolation, discharge, evaporation, transpiration, evapotranspiration, condensation
ALSO IS EVAPORATION AND TRANSPIRATION SAME THING AS EVAPOTRANSPIRATION
Answer:
water cycle, also called hydrologic cycle, cycle that involves the continuous circulation of water in the Earth-atmosphere system. Of the many processes involved in the water cycle, the most important are evaporation, transpiration, condensation, precipitation, and runoff. Although the total amount of water within the cycle remains essentially constant, its distribution among the various processes is continually changing.
What phenotype will an individual with a heterozygous genotype display?
Answer:
The dominant trait would be expressed physically (phenotype)
Kevin says that all components of the natural environment would be protected if all nations had strict laws in place. If this was the case, what is the main reason that international treaties or agreements would still be necessary?
A.
It would make sharing scientific information easier.
B.
Most polluters are large, multinational corporations.
C.
Pollution and wildlife do not respect national borders.
D.
Invasive species originate from around the world.
C. Pollution and wildlife do not respect national borders. Even with strict laws in place in individual nations, international treaties or agreements are necessary because environmental issues are often transboundary, affecting multiple countries and regions
two major classifications of transposable elements in the human genome are a. copia and p elements. b. sines and satellites. c. dna elements and retrotransposons. d. vntrs and strs.
The two major classifications of transposable elements in the human genome are: DNA elements and retrotransposons. The correct option is (c).
Transposable elements, also known as jumping genes or mobile genetic elements, are DNA sequences that can change their position within a genome. These sequences play a significant role in the evolution of genomes.
The two major classifications of transposable elements are DNA elements and retrotransposons. They are both capable of moving within the genome, but they use different mechanisms.
DNA elements: These elements use a "cut and paste" mechanism to move within the genome. They have an enzyme called transposase, which is responsible for the movement of the transposable element. There are two main classes of DNA elements: DNA transposons and Helitrons.
Retrotransposons: These elements use a "copy and paste" mechanism to move within the genome. They have an RNA intermediate, which is used to create a DNA copy of the retrotransposon that is then inserted back into the genome.
Retrotransposons have two subclasses: Long Terminal Repeat (LTR) retrotransposons and Non-LTR retrotransposons (also called LINEs and SINEs).
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three ways that CRISPR is making genetic engineering more accessible
Answer:
Precision and accuracy: CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) technology allows for precise and accurate editing of specific genes within a genome. This technology is much more efficient and effective than previous methods of genetic engineering, such as zinc-finger nucleases and TALENs, which were much more difficult and expensive to use.
Cost and accessibility: The cost of CRISPR technology has dropped dramatically since its discovery, making it more accessible to researchers and scientists. This has led to a proliferation of research in the field of genetic engineering, with more and more labs and institutions adopting CRISPR technology.
Flexibility: CRISPR technology can be used in a wide range of organisms, including bacteria, plants, animals, and even humans. This versatility has made it possible to study and edit genes in a variety of organisms, leading to new insights and discoveries in the field of genetics.
Explanation:
Create a story to highlight how the circulatory and respiratory work interdependently
Which of the following organisms in the arctic tundra ecosystem retains the least chemical energy fixed by photosynthesis?
a. arctic fox
b. caribou
c. snow goose
d. lichen
The lichen is the creature in the polar tundra ecosystem that fixes the least amount of chemical energy.
The symbiotic relationship between a fungus and an alga or cyanobacterium results in lichen. Lichen can endure harsh environments, but they grow slowly and are not very good at storing the energy produced by photosynthesis. In the polar tundra ecosystem, lichen makes up the base of the food chain and is a source of nutrition for herbivores like caribou and snow geese.
However, they have the lowest trophic level in the food chain since they retain the least energy. The arctic fox has a higher trophic level and maintains more chemical energy since it eats herbivores like caribou and snow geese.
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Charles Lyell proposed that the same processes occurring in nature today also occurred in the past. How did this idea influence Charles Darwin's research and development of the theory of natural selection?
It caused him to disregard fossils as potential evidence for change in populations.
It led him to compare populations in different parts of the world.
It led him to conclude that natural selection was a modern phenomenon.
It inspired him to breed populations to study how traits are inherited.
The idea proposed by Charles Lyell that the same natural processes occurring today also occurred in the past is known as uniformitarianism. This idea had a significant influence on Charles Darwin's thinking and research.
Explain Darwin Idea of uniformitarianism?
Darwin was fascinated by the geological work of Lyell and his idea of uniformitarianism. He applied this concept to biology, arguing that the natural world is in a constant state of flux and change. Darwin realized that if the processes of natural selection that he observed in nature were responsible for the diversity of life today, then they must have also been responsible for the diversity of life in the past.
Therefore, Darwin used the idea of uniformitarianism to support his theory of evolution by natural selection. He recognized that the same processes of variation, selection, and adaptation that occur in nature today also occurred in the past, leading to the evolution of species over time.
In conclusion, Lyell's idea of uniformitarianism was influential in shaping Darwin's thinking about the natural world, and it played a crucial role in the development of his theory of evolution by natural selection.
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Answer: Hey there! I got the answer just for that the answer is
“It inspired him to breed populations to study how traits are inherited.”
Explanation: Took the quiz :>
why has natural selection favored the evolution of double circulation in birds and mammals? group of answer choices because they cannot obtain as much oxygen from the air as reptiles and amphibians because they live in terrestrial environments because they use more energy than equivalent-sized reptiles and amphibians because they are less active than reptiles and amphibians because they are always larger than reptiles and amphibians
Natural selection has favored the evolution of double circulation in birds and mammals because they use more energy than equivalent-sized reptiles and amphibians.
What is natural selection? Natural selection is a process that occurs in nature whereby individuals that have traits that are well adapted to their environment survive and reproduce better than those that do not. The individuals who are better adapted are more likely to survive and reproduce, and their genes are passed down to their offspring.
Therefore, the process continues as the best-adapted individuals continue to survive and reproduce.
What is double circulation? Double circulation refers to the system of circulation that consists of two circuits that are both driven by the heart. One circuit is the pulmonary circulation, and the other is the systemic circulation. The pulmonary circuit carries deoxygenated blood to the lungs, where it is oxygenated, and then back to the heart.
The systemic circuit carries oxygenated blood to the body and then back to the heart.
Why has natural selection favored the evolution of double circulation in birds and mammals? Natural selection has favored the evolution of double circulation in birds and mammals because they use more energy than equivalent-sized reptiles and amphibians.
Double circulation, which delivers oxygenated blood directly to the body tissues, is more efficient than single circulation, which does not deliver oxygenated blood directly to the body tissues, and as a result, it allows birds and mammals to use more energy than reptiles and amphibians.
This is why natural selection has favored the evolution of double circulation in birds and mammals.
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Can nonsmokers hold their breath longer then people who smoke dependent variable
Because smokers' lungs are weak and likely not as robust as non-smokers' lungs, non-smokers can hold their breath for longer.
A nonsmoker is someone who has never smoked, yet who may have done so at some time in their lives. Those who have never smoked or who have smoked fewer than 100 cigarettes in their lifetime are also referred to as never-smokers.
A non-profit group in Canada called the Non-Smokers' Rights Association (NSRA) is committed to preventing tobacco use. It was established in Toronto by nurse Rosalee Berlin, and it immediately became a world authority on tobacco control problems, particularly cigarette sponsorship, tobacco advertising, and tobacco packaging.
The Smoking and Health Action Fund (SHAF), a registered charity in Canada, is its sibling non-profit organization.
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A swamp is more productive than a stream. Select the reasons (3) why.
a
Streams have too much salt water in them to be productive.
b
The water and oxygen in swamps is cycled, but not too quickly.
c
Swamps are not productive.
d
Rivers have water that flows too quickly.
e
Swamps have a moderate flow of water.
f
Streams don't get enough sunlight
A swamp is more productive than a stream. because b, e, and f reasons Swamps and streams are just two examples of aquatic ecosystems with distinct characteristics and productivity levels.
Swamps are often more productive than streams because of their unique characteristics. Swamps have a slower flow of water, which allows for the cycling of nutrients and oxygen to support a diverse range of plant and animal life. They also have a moderate flow of water, which allows for sediments and nutrients to settle and accumulate, creating a rich and productive ecosystem.
In contrast, streams can have a faster flow of water, which prevents nutrients and sediments from settling and accumulating. Additionally, the flow of water can prevent sunlight from penetrating to the bottom, limiting the amount of plant growth and productivity.
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When is a place considered to be
healthy?
when biodiversity is high
O when biodiversity is very low
O when there is no life
O when bacteria are gone
Answer:
A, When biodiversity is high.
Explanation:
High biodiversity indicates a wide range of species with diverse ecological roles, which promotes ecosystem stability and resilience to environmental disturbances. Greater biodiversity also ensures a more complex food web, increasing the availability of resources, and supporting more complex ecological interactions. Furthermore, diverse species provide critical ecosystem services such as nutrient cycling, water purification, and soil formation, enhancing the health of the environment and benefiting human well-being.
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curly hair in horses is recessive to normal hair. if 15% of a population of horses has curly hair, calculate the frequency of individuals homozygous dominant
The proportion of those who have normal hair is homozygous dominant in p2 = (0.106)2 = 0.0112, or around 1.12%.
What is the formula to determine whether a population is in Hardy-Weinberg equilibrium?Scientists must watch a population for at least two generations in order to determine if it is in Hardy-Weinberg equilibrium. Hardy-Weinberg When the allele frequencies in the population's two generations are equal, equilibrium is present.
What is calculable using the Hardy-Weinberg method?A population's genetic diversity may be calculated using the Hardy-Weinberg equation when it is in an equilibrium state. The Hardy-Weinberg equation is a key concept in population genetics that G. H. Hardy and Wilhelm Weinberg independently introduced in 1908.
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Question:
In a population of horses, curly hair is a recessive trait compared to normal hair. If 15% of the horses in the population have curly hair, what is the frequency of individuals that are homozygous dominant for normal hair?
Which of the following statements correctly describes the problems caused by invasive species like the Burmese python and European rabbit?
A
They create more habitats for native species.
B
They create a new food source for native species.
C
They bring diseases to the area.
D
They overpopulate and compete with native species for both space and food
They overpopulate and compete with native species for both space and food is the problems caused by invasive species like the Burmese python and European rabbit.
Option D is correct.
What is the most significant problem that invasive species cause?Industries, communities, and native cultures that depend on the country's natural resources are devastated when invasive species outcompete native plants and animals. Additionally, they degrade waterways, reducing recreational opportunities and affecting the quality of the water.
What is the primary driver of invasive species?Most of the time unintentionally, human activities spread invasive species. People and the things we use move quickly around the world, often bringing with them unwelcome species. Boats can convey amphibian organic entities in their stabilizer water, while more modest boats might convey them on their propellers.
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The loss of flying ability by the beetle is most probably the result of
The loss of flying ability by the beetle is most probably the result of genetic changes in the beetles.
Flying requires the coordinated action of many genes involved in the development of wings, muscles, and other structures involved in flight. If one or more of these genes undergoes mutations or changes, it can affect the ability of the beetle to fly. The loss of flying ability in beetles can have both positive and negative effects on their survival and reproductive success, depending on the specific environmental conditions they face.
Genetic changes can occur through a variety of mechanisms, including mutations, deletions, duplications, and chromosomal rearrangements. These changes can be caused by environmental factors, such as exposure to radiation or toxins, or can arise spontaneously during DNA replication or cell division. Over time, natural selection may favor beetles with reduced wings or flight muscles if these traits confer a fitness advantage in a particular environment.
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If you begin with a 400 gram sample of Rubidium-87 and only 100 grams
remain…
How many half-lives have gone by?
How old is the sample?
Answer:
200 g
Half-life of rubidium-87 = 4.8 x 10¹⁰ years.
Explanation:
The half-life formula that is given by `N=N_o(1/2)^(t/t1/2)`Where, N = remaining mass N_o = initial mass`1/2` = decay constant`t` = time elapsed`t1/2` = half-life We know that Rubidium-87 has a half-life of 48.8 billion years.
Therefore, using the half-life formula, we can find the time elapsed or the number of half-lives that have gone by. Given, Initial mass `N_o` = 400 g Remaining mass `N` = 100 g Half-life `t1/2` = 48.8 billion years Now, using the formula, we have:100 = 400(1/2)^(t/48.8 billion) Simplifying the equation:1/4 = (1/2)^(t/48.8 billion)
Taking the logarithm of both sides:log(1/4) = log[(1/2)^(t/48.8 billion)]Using the logarithmic property: log(1/4) = (t/48.8 billion)log(1/2)log(1/4) = -2log(1/2)Therefore, we have:-2 = t/48.8 billion Multiplying both sides by 48.8 billion:48.8 billion x -2 = tt = -97.6 billion years Since time cannot be negative, it means there is an error somewhere.
Hence, the initial mass must have been 100 g. Using the same formula, we have:100 = 100(1/2)^(t/48.8 billion)Simplifying the equation:1 = (1/2)^(t/48.8 billion)Taking the logarithm of both sides: log(1) = log[(1/2)^(t/48.8 billion)]0 = t/48.8 billion
Multiplying both sides by 48.8 billion :t = 0Therefore, the number of half-lives that have gone by is 0 and the sample is 0 years old.
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Are anole lizards and salamanders co-evolution
First Answer:
Yes, anole lizards are co-evolution!
Explanation:
I couldn't find any explanation for this one! (I hope you can trust me) This is a link. But this will help you get details yourself. Don't report this please, it is actually a real reliable website about wild life. wildlife.org
Second Answer:
Yes, salamanders are co-evolution!
Explanation:
By the time the salamanders reached the southernmost part of California, the separation had caused the two groups to evolve enough differences that they had become reproductively isolated. In some areas the two populations coexist, closing the "ring," but do not interbreed. They are as distinct as though they were two separate species.