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
SSSSS [86.1K]
3 years ago
13

How long ago did the common ancestor of all the organisms on this phylogenetic tree exist?

History
1 answer:
Anton [14]3 years ago
7 0
In biology<span> and </span>genealogy<span>, the </span>most recent common ancestor<span> (</span>MRCA<span>, also </span>last common ancestor<span> LCA, or </span>concestor[1]<span>) of any set of </span>organisms<span> is the most recent individual from which all organisms in a group are directly </span>descended<span>. The term is also used reference to the ancestry of groups of </span>genes<span> (</span>haplotypes) rather than organisms. <span>The age of the </span>human MRCA<span> is unknown. It is necessarily younger than the age of both Y-MRCA and mt-MRCA, estimated at around 200,000 years, and it may be as recent as some 3,000 years ago.</span>
You might be interested in
Which works of art by the Olmec civilization are considered its most recognizable artifacts?
DaniilM [7]
<span>The most striking legacy of the Olmec civilization must be the colossal stone heads they produced. These were carved in basalt and all display unique facial features so that they may be considered portraits of actual rulers. Hope this helps. Have a nice day.</span>
3 0
3 years ago
Assess the requirements established by black codes in the South. In addition, speculate about their connection to what would lat
amid [387]

Answer:

The Black Codes and Jim Crow Laws

After the United States Civil War, state governments that had been part of the Confederacy tried to limit the voting rights of black citizens and prevent contact between black and white citizens in public places.

Colored Water Fountain

The effort to protect the rights of blacks under Reconstruction was largely crushed by a series of oppressive laws and tactics called Jim Crow and the black codes. Here, an African-American man drinks from a water fountain marked "colored" at a streetcar terminal in Oklahoma City, Oklahoma in 1939.

Black codes and Jim Crow laws were laws passed at different periods in the southern United States to enforce racial segregation and curtail the power of black voters.

After the Civil War ended in 1865, some states passed black codes that severely limited the rights of black people, many of whom had been enslaved. These codes limited what jobs African Americans could hold, and their ability to leave a job once hired. Some states also restricted the kind of property black people could own. The Reconstruction Act of 1867 weakened the effect of the black codes by requiring all states to uphold equal protection under the 14th Amendment, particularly by enabling black men to vote. (U.S. law prevented women of any race from voting in federal elections until 1920.)

During Reconstruction, many black men participated in politics by voting and by holding office. Reconstruction officially ended in 1877, and southern states then enacted more discriminatory laws. Efforts to enforce white supremacy by legislation increased, and African Americans tried to assert their rights through legal challenges. However, this effort led to a disappointing result in 1896, when the Supreme Court ruled, in Plessy v. Ferguson, that so-called “separate but equal” facilities—including public transport and schools—were constitutional. From this time until the Civil Rights Act of 1964, discrimination and segregation were legal and enforceable.

One of the first reactions against Reconstruction was to deprive African-American men of their voting rights. While the 14th and 15th Amendments prevented state legislatures from directly making it illegal to vote, they devised a number of indirect measures to disenfranchise black men. The grandfather clause said that a man could only vote if his ancestor had been a voter before 1867—but the ancestors of most African-Americans citizens had been enslaved and constitutionally ineligible to vote. Another discriminatory tactic was the literacy test, applied by a white county clerk. These clerks gave black voters extremely difficult legal documents to read as a test, while white men received an easy text. Finally, in many places, white local government officials simply prevented potential voters from registering. By 1940, the percentage of eligible African-American voters registered in the South was only three percent. As evidence of the decline, during Reconstruction, the percentage of African-American voting-age men registered to vote was more than 90 percent.

5 0
3 years ago
Why did so many people turn to Christianity after the fall of the western Roman empire?
notka56 [123]
For a rise of a new region
4 0
3 years ago
Read 2 more answers
What was the largest and most costly battle ever fought in the Indian territory
lianna [129]
Battle of Honey Springs on July 17 1863
6 0
3 years ago
Conservative Republicans wanted to use traffis to protect American industry from
Alisiya [41]
They wanted to use tariffs to protect local manufacturers and producers from foreign competition. When you increase the tariff then importing costs more and people don't buy imported goods but buy local goods because they are cheaper. This helps domestic manufacturers and producers.
4 0
3 years ago
Other questions:
  • The House of Representatives has 1 representative per state , True or False?
    15·2 answers
  • During the 19th century, congress was the dominant national institution, but during the 20th century, the president has become t
    12·1 answer
  • What advantage did the patriots held during the revolutionary war
    11·1 answer
  • How did the founders solve the problem of a too powerful military
    9·1 answer
  • The story behind supergirl
    13·2 answers
  • PLEASE HELP!
    6·1 answer
  • HELP HURRY ASAP PLZ BRAINLIEST
    5·2 answers
  • How can you change an amendment?​
    8·1 answer
  • Which of the following was not a contribution made by georgia during WW1
    13·1 answer
  • EXPLAIN " THE END DOES NOT JUSTIFY THE MEANS"
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!