1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
natulia [17]
3 years ago
15

Describe the four reasons evolution occurs

Biology
1 answer:
Liula [17]3 years ago
4 0

Answer:

Organisms produce more offspring than actually survive.

Organisms can die from many causes: disease, starvation, and being eaten, among other things. The environment can't support every organism that is born. Many die before they are able to reproduce. One hundred (100) beetles can produce 6.1 x 1028(61 with 27 zeros after it) offspring in only 82 weeks (less than two years). Each beetle weighs 10 mg, and if they all survive, their total weight after 82 weeks would be 6.1 x 1021 (61 with 20 zeros after it) metric tons, equal to the weight of the entire earth. Obviously, their environment can't support all of these beetles, and many of them die.

The fish eggs at left are only a small fraction of those laid by a single fish. If all of the fish hatched and each of them laid as many eggs, which all hatched as well, there would be too many fish for the fishes' environment to support. [2]

2. Every organism must struggle to survive.

One reason that not all organisms survive is that there are not enough resources, things that they need, to go around. Organisms must struggle to get what they need to survive, competing against other organisms that want the same things they do. They also have to struggle to get away from predators and to overcome disease. For example, a fox struggling to catch a rabbit, which struggles to escape. As explained in part one, not all of them make it.

3. There is variation within a species.

Not all of the individuals in a species are exactly the same. There are variations, differences, among members of a species. If you look at the spots on several different ladybugs, or the stripes on zebras, you will notice that they don't all have the same number or arrangement of spots or of stripes. In addition to these easily visible variations, there are differences in skill and behavior, such as differences in how fast the zebras can run. If organisms were all the same, none would be better suited than any other, and selection could not occur.

4. Some variations allow members of a species to survive and reproduce better than others.

If an organism has a trait that helps it survive or reproduce, it is more likely to survive and be able to reproduce. A faster cheetah is more likely to catch a gazelle and survive, and a faster gazelle is more likely to escape the cheetah and survive. A showier flower is more likely to be noticed by a bee, which enables it to reproduce. A thornier cactus is more likely than other cactuses to be left alone by animals, rather than be eaten and die.  

5. Organisms that survive and reproduce pass their traits to their offspring, and the helpful traits gradually appear in more and more of the population.

Most of an organism's traits are passed on to its offspring. If more of the organisms with the helpful trait survive, then in the following generations, more and more of the population have that trait. If there are some faster cheetahs and some slower cheetahs, the faster cheetahs will be better able to catch food and survive. With more of the slower ones dying before they can reproduce, and more of the faster ones surviving and reproducing, over generations the population on the whole will gradually become made up of faster cheetahs.

Explana

You might be interested in
The solid, outermost layer of the Earth is ___________.
Blizzard [7]

Answer

d.crust

Explanation

because he covered the layer of the earth

6 0
2 years ago
Read 2 more answers
A red flower (RR) and a red flower (Rr) have the same:
liraira [26]
The flower would be Genotype
3 0
3 years ago
Read 2 more answers
Pls an answer asap!!
Paul [167]

Answer:

B

Explanation:

4 0
2 years ago
each of these terms refers to a stage in the human menstrual cycle except a. ovulation b. luteal phase c. corpus phase d. follic
baherus [9]
Each of these terms refers to a stage in the human menstrual cycle except <span>corpus phase</span>
4 0
3 years ago
If there are no differences between the amino acid sequences in the cytochrome c protein of humans and chimpanzees, why aren't w
kobusy [5.1K]
Because it doesn't go together
7 0
3 years ago
Other questions:
  • The equator is a line of latitude true or flase
    9·2 answers
  • In the 1950s, Christian Anfinsen demonstrated the renaturation of the protein ribonuclease (RNase) in vitro. After reduction and
    9·1 answer
  • Which type of transport requires energy to move a molecule?
    10·1 answer
  • The region of the body surface monitored by a pair of spinal nerves is known as a __________.
    10·2 answers
  • Is are blood blue or red?
    7·1 answer
  • Which is NOT a volcanic hazard?
    14·1 answer
  • Which phylum has members that secrete a hard, calcium carbonate shell?
    12·1 answer
  • Proper folding of proteins is essential for their biological activity. In general, the functional conformation of a protein is t
    5·1 answer
  • The sarcoplasmic reticulum wraps like a sleeve around the myofibril and stores and releases calcium
    11·1 answer
  • Elements bond together to make molecules essential for living things. Which of the following is used in organism as storage comp
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!