Two morphologically identical Drosophila populations live in Lower Nahal Oren, Mount Carmel, Israel. There are two slopes of a valley that face each other and drosophila live on both slopes (they share a common ancestor). The environment is very different even though they are very close. In the center of the valley is an area in which flies from each side have an opportunity to mate. (an aside: This is frowned upon by fly society buy these tiny Montagues and Capulets persist). Evaluate each scenario:

Answers

Answer 1

Answer:

There are two possible scenarios

Scenario 1) Genetic flow is acting on these populations

Scenario 2) The original population has recently diverged

Explanation:

Scenario 1:

These two populations of flies should probably express some phenotypic difference due to the environmental condition on each slope. Remember that the phenotype is the product of interaction between the genotype and the environment. However, the difference between populations would exist if they were isolated and separated by an ecological or biological barrier. The barrier would impede genetic flow, and each population would have its particular genetic charge and phenotype.

In the exposed situation, we know that each population inhabits a slope. And that the slopes differ in the environmental conditions. But in the center of the valley, these two populations get to meet and mate. The valley is acting as a corridor between both groups and allows the genetic flow to occur.

Let us remember that gene flow is an evolutive strength only if

there exists migration from one population to the other, and the allelic frequency in one generation is different from the allelic frequency in the next generation.

Genetic flow acts homogenizing the allelic frequencies between the two populations, and it might introduce variability into the new one. For genetic flow to be possible, there needs not only the movement of the genes from one population to the other but also the reproduction process on the new population. Hence, it involves an interaction between the dispersion pattern and the reproductive system.

Individuals from both groups get to mate in the valley, leaving fertile offspring. The offspring, carrying genes from both populations, are included in one or the other group, where they will reproduce. In each population, the frequency of genes of the other group increase with time as the flies keep mating. Eventually, genetic flow homogenizes the variability between both populations, making them look similar.

Scenario Two:

It might be an early dispersion event in which the common ancestor of both populations used to inhabit the center of the valley. With time, and as the original population got bigger, dispersion took a significant role. Flies began moving into both slopes. Even though each area has different environmental conditions, there has not been enough time for these animals to adapt morphologically to each side, so they still look identical. Also, as it is an early event, these two new groups are not separated yet, so they have not developed biological barriers between them, and individuals can still mate in the center of the valley.  


Related Questions

The diagram shows the life cycle of a pine tree.​

Answers

Answer:i would hink it was d cause you can see the graph and what happening and there ends up to grow a tree at the end

Explanation:

pls mark brainliest

A scientist wants to determine whether a mutant phenotype is due to the loss of gene C or gene D, which are both deleted in a mutant fly with abnormal eyes. Mutant flies with that have a transgenic gene C have wild-type eyes, whereas mutant flies that have a transgenic gene D have abnormal eyes. What can be concluded from these results

Answers

Answer:

a transgenic copy of the gene C is sufficient to restore normal eye development

Explanation:

In genetics, there are diverse approaches to determining a gene's function. For example, it is possible to use a complementation test to determine loss-of-function recessive mutations when it is unknown if such mutations fall in the same or in different genes. Similarly to the generation of loss-of-function phenotypes, it is possible to insert a gene and thus produce a gain-of-function mutation that restores normal gene function (i.e., to restore the wild phenotype). Moreover, transgenic organisms refer to genetic engineering techniques by which any foreign or modified gene is inserted in the genome of an organism, which can also be used to study gene function. In this case, the restoration of the normal phenotype (wild-type eyes) is associated with the expression of the transgenic gene C, thereby evidencing that the gene C is required for normal eye development. In the last years, transgenic models have shed light on developmental pathways and on gene function.

Phenylketonuria causes a severe cognitive disability due to the inability to metabolize phenylalanine. It is an autosomal recessive disorder. About one in 12,000 newborns in Massachusetts are afflicted with the disease, skewed higher than the general US population due to more Irish-Americans. Assuming the gene is in Hardy-Weinberg equilibrium, the frequency of the carriers (heterozygotes) in Massachusetts would be calculated to be...

Answers

Answer:

The frequency of the carriers (heterozygotes) in Massachusetts is 0.018

Explanation:

Due to technical problems, you will find the complete explanation in the attached files

Katie is camping with her family. She forgot her gloves. Now her hands are cold.
How can Katie keep her hands warm?
OA
Katie can stick her hands in cold water.
ОВ.
Katie can hold a flashlight in her hands.
OC.
Katie can rub her hands together.
OD. Katie cannot make her hands warm.

Answers

Answer:

Katie can rub her hands together

Explanation:

The friction of her hands rubbing together will create heat.

Design an experiment to test the role of thyroxine in helping the body adjust to cold temperatures. Describe the overall investigation to be done, the variables to be changed, the variables to be kept constant, the subjects to be used, the control and experimental conditions to be used, the type of data collected, and how the data will be collected. Explain how these data can be used to justify the conclusion that thyroxine is involved in adjusting body temperature in response to cold. (9 points)

Answers

Answer:

- Hypothesis: thyroxine gene is responsive to low temperatures, thereby its transcript level is higher in cold climates

- Subjects of study: gene expression data collected from individuals from countries with different climates  

- Experiment: to determine thyroxin gene expression level by Real-Time PCR (RT-PCR) in individuals living in cold climates (e.g., Iceland) versus individuals living in warmer climates (e.g., Puerto Rico)

- Independent variable: temperature

- Dependent variable: thyroxin transcript level  

- N sample: 500 individuals of each population  

- Control group: individuals living in the same climate conditions but from different countries. It can be done by collecting gene expression data from individuals living in another country. For example, both Fairbanks (Alaska) in the USA and Reykjavik in Iceland are at 64 degrees N latitude, and thereby these cities have similar climates

- Constant variable: all data collected from individuals of adult age (age range: 20-30 years)  

Explanation:

The scientific method is a sequential process that consists of making hypotheses in order to explain observations from the real world, make predictions based on the working hypotheses, carrying out experiments based on those predictions, test the predictions and draw conclusions based on the results obtained. In an experiment, the independent variable isn't changed by the other variables, while the dependent variable is the variable being measured in the experiment. A constant variable does not change during the experiment. Moreover, a control group is a particular group to which comparisons are made during the experiment (the control group isn't exposed to the independent variable, and therefore any change in the experimental groups can be compared with the control). In this case, it is expected to measure thyroxine expression levels in 500 individuals from each country by RT-PCR (RT-PCR technique is used to measure the amount of mRNA of a target gene of interest). Subsequently, it is possible to determine if the differences in the thyroxin gene expression levels between populations (i.e., individuals living in Iceland vs individuals living in Puerto Rico) are statistically significant to confirm that thyroxin gene activity is increased in response to cold exposure. Finally, the control group can be used to determine if observed differences in gene expression are irrefutably correlated with cold conditions.

which three layers of the sun make up the suns atmosphere

a - plasma, corona, convection zone
b - radiative zone, convection zone, core
c - core, convection zone, chromosphere
d - photosphere, chromosphere, corona

Answers

Answer:

B

Explanation:

Or  - radiative zone, convection zone, core

Sun's atmosphere consists photosphere, chromosphere, and corona. Hence option d is correct.

What are the three layers of the suns atmosphere?

Sun is divided into two parts internal sun and atmosphere. In sun's atmosphere, it consists photosphere- the visible surface of the sun,

chromosphere- it is the transition state between the photosphere and corona.

The outermost hot shell of the atmosphere is the corona, these there layers males the sun's atmosphere.

These three layers make the sun's atmosphere apart from its internal structure, core, radiation zone, and convection zone these are three interior layers of the sun.

Therefore option d corona, chromosphere, and photosphere are correct.

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Order the steps in the process of fertilization.

Answers

Answer:

The stages of fertilization can be divided into four processes:

1) sperm preparation,

2) sperm-egg recognition and binding,

3) sperm-egg fusion and

4) fusion of sperm and egg pronuclei and activation of the zygote.

Which sequence list matter from smallest to largest

A:molecule-atom-tissue-organ system

B: atom-molecule-tissue-organ

C:atom-molecule-organ system-tissue

D:atom-organ-molecule-organ system

Answers

Answer:

B

Explanation:

Atoms are smaller than molecules, then the tissue comes before the organ

B is the best answer to go with

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Answers

Answer:

small fishes--tuna fish--dead animal material---crabs

Explanation:

follow the arrows from small fishes to crabs

Answer:

Answer is below

Explanation:

Small fish ---> Tuna Fish ---> Dead Animal Material ---> Crabs

This shows the path specifically followed from the small fish to the crabs

Herd behavior benefits wildebeests by (1 point)
O increasing the number of resources availablė.
O allowing altruistic behavior.
O decreasing the chance of spreading disease.
O helping individuals find mates.

Answers

Answer:

helping individuals find mates.

Explanation:

took test

The correct answer is option d helping individuals find mates.

We can begin the solution for this one with a method of elimination.

2 cannot be proper due to the fact herding conduct nearly definitely will increase the possibility of spreading diseases. For 3, having extra people in a set affects more opposition and consequently fewer assets so we are able to get rid of that one as well.Then the selection is among 1 & four. You ought to make a controversy for four however it appears a piece indistinct concerning the precise advantages of altruistic conduct. I'd argue that altruistic conduct is extra of an effect than a motive of sociality/herding.Choice 1 is a not unusual place reason for sociality in animals. In species that do not stay in social organizations trying to find buddies may be very high priced in phrases of time and electricity and publicity to predators. It's a whole lot less difficult to discover a mate while many people are residing in proximity. Because replica is this kind of essential a part of the existence cycle I consider 1 is the exceptional answer.

What is herd behavior?

Herd conduct is the conduct of people in a set appearing together without centralized direction. Herd conduct happens in animals in herds, packs, chook flocks, fish faculties, and so on, in addition to in humans.

Thus it is clear that the option that helps individuals find mates is the correct answer.

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Soooo... anyone have an essay on the impact of climate change on the oceans they’d like to share?? :)
I need ideas!!!

Answers

Answer:

Here's a paragraph that you can add !

Explanation:

When greenhouse gases capture more solar radiation, the oceans consume more heat, resulting in higher sea surface temperatures and increasing sea level. Changes in water temperatures and tides caused by climate change will cause changes in global climate patterns.

Şermin yaşar gelirken ekmek al kitabı özet acilll​

Answers

Answer:

Kitabın Yazarı:Şermin YaşarKitap Türü:Öykü/HikayeYayınevi:Doğan KitapçılıkYayınlandığı Yıl:2019 (19-10-2019)Sayfa Sayısı:196ISBN:9786050966534Kitap Puanı:8 / 10 | Yorum: 22

Explanation:

What!????????? I don’t understand this

Complete the sentence using the correct term.
-blank- technology allows us to create combinations of genes from two different species.

Answers

Answer:

Cloning technology

Explanation:

With cloning technology we can replicate and combine different genes to study, save lives, and create new species

Ecosystems: Relationships: Question 4
Look at the table.
Environmental Level Content of the Level
1
a fallen tree rotting in a forest
N
all the living things in the fallen tree
3
the ants in the fallen tree
4
an ant
Which level of the table is best labekd organism?
Select one:

Answers

Answer:

an organism is any living thing..including ants...

how can a brick wall model as a group of plant cells

Answers

Answer:Like a brick wall, your body is composed of basic building blocks, and the building blocks of your body are cells.For example, epithelial cells protect the outside surface of the body as part of the skin and cover the organs and body cavities within. Bone cells build up bones to provide support for the body.

Explanation:

wrote an essay on it

I really need help please somebody...

Answers

i think 75% due to some may have no horns bc its non dom

Answer:

first choice: 25%

Explanation:

when crossing Aa x aa, there is a 25% chance that the outcome will be Aa, giving the resulting cattle offspring horns. Hope this helps!

Imagine two populations of penguins live in the same ecosystem. One population begins to exchange stones as a mating ritual while the other population begins to dance by shifting from one foot to the other. Individuals from each population will only mate with individuals that display the appropriate mating ritual. Which type of reproductive isolation mechanism does this scenario describe?(1 point)

Behavioral Isolation

Geographic Isolation

Temporal Isolation

Habitat Isolation

Answers

Answer:

i think its behavioral

Explanation:

Answer:

The answer would be Behavioral Isolation.

Explanation:

I did the Connections Academy Quick Check and it said it was correct.

Protists are
A. the simplest of eukaryotes
B. members of a single kingdom
C. the simplest of eukaryotes, and are generally aquatic
D. the simplest of eukaryotes, generally aquatic, and members of a single kingdom
E. generally aquatic

Answers

Answer:

D

Explanation:

that is the answer 101010101010101001

answer the question that follows. In which category of animals do salamanders fall? A.fish
B.reptiles
C.invertebrates
D.amphibians

Answers

D.amphibians: Salamanders belong to the Salamandroidea family and belong to the class of Amphibia. Salamanders have several other names including mud puppy, water dog, triton and spring lizard.

identify Whether the flu is a viral or bacterial in nature.
Are viruses living or non-living?
Would antibiotics be helpful towards the influenze virus structure.

No Links Pleaseoduce by the process of

Answers

Virus are considered to be non living
No antibiotics won’t be helpful towards influenza virus it can inturn result to antibiotic resistance
Flu is viral

Answer:

Viruses are Non- living they can't keep themselves in a stable state, they don't grow, and they can't make their own energy. Antibiotics won't help, and their side effects could cause harm. Because flu is a viral illness, antibiotics won't help to treat it.

Explanation:

What hormones stimulate the cycle of egg or sperm production?

Answers

Answer: The main reproductive hormones are estrogen and testosterone. Once a girl enters puberty, estrogen matures the eggs in the ovaries. These are then released at regular intervals during the menstrual cycle. Testosterone stimulates the production of sperm in men.

Explanation:

You burn a log on a fire. You use the fire to warm yourself and to light up the
room to read a book. Which energy transformation is taking place?

A. Chemical energy is transformed to nuclear energy and thermal
energy
B. Chemical energy is transformed to light energy and thermal
energy
C. Thermal energy is transformed to light energy and chemical
energy
D. Nuclear energy is transformed to potential energy and thermal
energy.

Answers

Answer:

b) is the the answer

Explanation:

hope it helps

state three features of myriapods that can be used to distinguish them from other arthropods​

Answers

Answer:

Mandibles (lower jaw) and maxillae (upper jaw)

Two body sections (head and trunk)

One pair of antennae on the head

Explanation:

hope this helps! have a great day / night

Although Myriapods share many characteristics with other arthropods, they distinguish for having an elongated and multisegmented body, one or two pairs of legs per segment, two antennae, and rolling-up ability

----------------------------------------  

As the name refers to, Myriapods have many feet. They characterize because their bodies are very elongated and divided into multiple segments. From each of the rings, emerge one or two pairs of legs.

As every arthropod, their bodies are segmented and covered by a cuticle for protection and to avoid dehydration.

Their heads carry two antennae, ocellus, and a mouth with prominent buccal appendixes. Some of them might be poisonous.

They can be slow when moving, but they are well-adapted to move through leaves and other organic material. But because they move slowly, they need a protection strategy to avoid predation. This strategy is rolling. They can roll up, and remaining like a boll, until the predator leaves.

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Please and thank you!

Answers

Answer:

A gene mutation

Explanation:

DNA nucleotide sequence is unique

What farming practices have depleted grasslands in North America?

Answers

Answer:

Cultivation of crops and tillage practices.

Explanation:

Farming of crops and tillage practices on the grasslands depleted grassland that are present across North America because the lands are converted and used for the production of food crops in order to fulfill the feed the existing population. More and more land is converted from grassland to the cultivation of crops that leads to lower area for the grazing of animals which results in decrease population of animals such as sheep, goat and cow etc which depends n these grazing regions for food.

Explain why atp is important in biochemical reactions

Answers

Answer:

ATP releases energy (ATP + H2O --> ADP + P + energy) and in order for things like active transport to happen ATP is required.

The machine that removes small plants from plug trays and transplants them
directly to pots is called which of the following?
a. automated seeder
b. automated pot filler
c. automated transplanter
d. automated plugger

Answers

Answer:

anwser is

C. automatic transplanter

hope it helped

Which of the following functions in multicellular organisms is similar to the function of DNA in unicellular organisms?
A.
Inheritance of traits


B.
Cell respiration


C.
Cell digestion


D.
Protein synthesis

Answers

A. Inheritance of traits

Both single and multi-celled organisms embrace a functional unit of life, known as “Cells”. Both of them consist of plasma membrane and cytoplasm. They carry similar features by containing DNA and ribosomes for the gene expression. All known forms of life store their genetic information using DNA, and with a few exceptions the code is universal.Both have basic unit of life (cell). Which means they both ingest food ,respire, and get rid of waste.Multicellular organisms are bigger than unicellular organisms. Unicellular has a single cell but multicellular have more than one cell.

Thus, option A is correct.

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What is the name of the cycle that develops during these changes?

Answers

what are these changes?

is it the growth or?

Could you tell us the changes?

Which piece of evidence would best support the argument for kin selection as a mechanism for the evolution of altruistic
behavior? (1 point)
O a penguin protects its chick from seagulls
O a hippo stops a crocodile from eating an antelope
O a clown fish helps clean parasites off of a sea anemone
O an antelope gets separated from the herd and killed by predators

Answers

Answer:

1. A penguin protects its chick from seagulls*

2. Data collected from a controlled experiment that has been reproduced in several different labs

3. Helping individuals find mates.

4. Surround prey

5. Data showing that only distantly related individuals are most likely to perform altruistic behaviors in order to protect each other

Explanation:

100% Group Behavior Quick Check

Good luck! ♡

The piece of evidence which would best support the argument for kin selection as a mechanism for the evolution of altruistic  behavior is: A. a penguin protects its chick from seagulls.

Altruism can be defined as a phenomenon in which a living organism promote another organism's welfare, especially at its own detriment or disadvantage.

Hence, altruism is an act in which a living organism show selfness and concern for another organism's predicament, even at a risk or cost to itself.

In Evolutionary biology, a living organism is considered to be altruistic  in nature, if its behavior is beneficial to other living organisms.

Based on kin selection, a living organism is considered to behave altruistically when its behavior is beneficial to organisms in its family or organisms that are directly related to it.

For example, a penguin which protects its chick (offspring) from seagulls best support the argument for kin selection as a mechanism for the evolution of altruistic  behavior

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