Evolution Mechanics and Earth's History

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Questions and Answers

A researcher observes that a specific plant species grows taller in sunny locations compared to shady ones. Following the scientific method, what would be the most logical next step?

Disregard the observation as a mere coincidence.
Immediately publish the observation in a scientific journal.
Conclude that sunlight is essential for the growth of all plant species.
Formulate a hypothesis about the relationship between sunlight and plant growth. (correct)

Which of the following is NOT a primary indicator of the Great Acceleration within the Anthropocene epoch?

Significant rise in atmospheric methane levels.
Decline in the rate of new technology patents filed globally. (correct)
Increasing ocean acidification.
Exponential increase in global GDP.

A scientist is analyzing data from an experiment testing the effect of a new fertilizer on crop yield. The initial hypothesis was that the fertilizer would increase yield by at least 15%. The results show an average increase of 12%, but with a high degree of variability among individual plants. What is the most appropriate conclusion?

The hypothesis is supported; the fertilizer is effective.
The data neither fully supports nor rejects the hypothesis; further investigation is needed. (correct)
The experiment is flawed and should be discarded immediately.
The hypothesis is rejected; the fertilizer has no effect on crop yield.

Considering the alarming rate of species extinction during the Anthropocene, which group is currently facing the most significant threat, according to the provided content?

Amphibians (D) Signup and view all the answers

How does the concept of the Anthropocene challenge traditional geological time scales?

By suggesting that human activities are now a dominant force shaping the planet. (B) Signup and view all the answers

Which of the pesticide generations is most likely to cause unintended harm to non-target species such as bees, due to its mechanism of action?

Third generation: neonicotinoids. (A) Signup and view all the answers

What is the most likely outcome of a farmer continually applying the same pesticide to a field year after year?

Development of a pesticide treadmill, requiring more potent chemicals. (D) Signup and view all the answers

The flipper of a seal, the wing of a bat, and the hand of a human have similar bone structures. What does this suggest about their evolutionary relationship?

They share a common ancestor but have adapted for different functions. (B) Signup and view all the answers

Snakes have small, unused leg bones. Which of the following statements best explains the presence of these vestigial structures?

Snakes evolved from an ancestor that had legs. (D) Signup and view all the answers

Pakicetus and Aetiocetus are examples of transitional species in whale evolution because:

they exhibit characteristics intermediate between earlier land mammals and modern whales. (A) Signup and view all the answers

Which species concept relies primarily on observable and measurable phenotypic differences?

Morphological Species Concept (D) Signup and view all the answers

Two species of frogs live in the same pond, but one breeds in early spring and the other in late summer. What type of reproductive isolation is this?

Temporal Isolation (D) Signup and view all the answers

In which scenario would the Ecological Species Concept be MOST applicable?

Identifying cryptic species with similar morphology but different resource utilization. (A) Signup and view all the answers

A population of plants with a mutation that causes a change in floral structure preventing pollination by the original pollinator species is an example of what?

Mechanical Isolation (C) Signup and view all the answers

Which of the following scenarios describes hybrid breakdown?

Two species mate and produce fertile offspring, but subsequent generations are infertile. (A) Signup and view all the answers

What is a key characteristic of gynogenetic species like the Amazon molly?

They require sperm from another species to stimulate egg development, but do not incorporate the other species’ DNA. (B) Signup and view all the answers

Which condition is essential for allopatric speciation to occur?

Physical separation that prevents gene flow between populations. (A) Signup and view all the answers

Given two populations that can interbreed and produce fertile offspring in the lab, but rarely interact in nature due to different habitat preferences, which species concept would likely classify them as separate species?

Ecological Species Concept only (A) Signup and view all the answers

If scientists discover a new species of plant that reproduces primarily through self-fertilization but occasionally outcrosses with nearby plants, what term best describes this species’ reproductive strategy?

Androdioecious (C) Signup and view all the answers

In a ring species, what reproductive interaction is typically observed?

Individuals can breed with their immediate neighbors, but not with those at the opposite end of the ring. (B) Signup and view all the answers

What is the primary distinction between a subspecies and a species?

Subspecies do not exhibit reproductive isolation, while species do. (A) Signup and view all the answers

What evolutionary processes are common to all three modes of speciation (allopatric, parapatric, and sympatric)?

Mutations, genetic drift, and natural selection. (B) Signup and view all the answers

What is a key characteristic of hybrid zones?

They offer a locale that can examine completion between different genotypes. (D) Signup and view all the answers

How does parapatric speciation differ from allopatric speciation?

Parapatric speciation occurs along an environmental gradient without complete spatial separation, while allopatric requires complete spatial separation. (B) Signup and view all the answers

What is the distinguishing feature of sympatric speciation?

It involves the evolution of reproductive isolation within a single, initially panmictic population. (A) Signup and view all the answers

What is the underlying mechanism that leads to two distinct sets of DNA in a chimaera?

The fusion of two independently developing embryos at a very early stage. (D) Signup and view all the answers

Which characteristic is present in Gnathostomata but absent in its outgroup, Agnatha?

Jaws (B) Signup and view all the answers

In a phylogenetic tree of vertebrates, which species would be placed closest to the common ancestor, given the following distribution of traits (1=present, 0=absent): jaws, bipedalism, amniotic egg, hair?

Species with: 1, 0, 0, 0 (B) Signup and view all the answers

A phylogenetic tree that includes an ancestral species and all of its descendants is known as what?

Monophyletic (C) Signup and view all the answers

In the owl breeding scenario, mitochondrial DNA differences are used to determine the closest species. If species A has 5 differences, species B has 12 differences, species C has 8 differences, and species D has 2 differences, which species is most suitable for breeding based solely on this mitochondrial DNA data?

Species D (A) Signup and view all the answers

What is the principal of maximum parsimony primarily used for in phylogenetic analysis?

Choosing the simplest, most likely cladogram among multiple possibilities (D) Signup and view all the answers

Consider an ancestral DNA sequence `AGTC`. Three species evolved from this ancestor with the following sequences: Species 1: `AGAC`, Species 2: `GGTC`, Species 3: `AGTC`. According to the principle of maximum parsimony, which cladogram is most likely to be correct?

Cladogram requiring 3 changes (A) Signup and view all the answers

An ancestral population with the following traits (jaws, lungs, amniotic egg) gives rise to 3 descendant populations. Population A loses lungs, Population B loses jaws and amniotic egg, Population C loses the amniotic egg. Based solely on the traits that are lost, arrange the descendant populations based on relatedness to the ancestor, from most to least related.

A, C, B (A) Signup and view all the answers

You are constructing a phylogram of several turtle species using genetic data. After analyzing the data, you find that different tree arrangements are possible. According to the principal of maximum parsimony, how should you approach this situation?

Choose the tree arrangement that requires the fewest evolutionary changes. (D) Signup and view all the answers

Which of the following is the MOST likely consequence of widespread ocean anoxia during the Permian period?

A significant decrease in the population of organisms requiring dissolved oxygen. (A) Signup and view all the answers

During which geological period did the first forests and tetrapods appear?

Devonian (B) Signup and view all the answers

Which of the following is NOT a primary threat to biodiversity, as represented by the acronym HIPPO?

Plate Tectonics (B) Signup and view all the answers

What significant event occurred approximately 2.7 BYA, marking a major transition in Earth's atmosphere during the Archean eon?

The Great Oxygenation Event (C) Signup and view all the answers

How did the breakup of Pangea during the Mesozoic era MOST likely contribute to increased biodiversity?

By creating new geographic barriers, leading to allopatric speciation (C) Signup and view all the answers

The rise of eukaryotic cells is theorized to have occurred through endosymbiosis during which eon?

Proterozoic (C) Signup and view all the answers

During which period within the Paleozoic era did the 'Cambrian Explosion' occur, leading to a rapid diversification of complex organisms?

Cambrian (D) Signup and view all the answers

Which of the following occurred during the Quaternary period?

The age of ice ages (B) Signup and view all the answers

What significant evolutionary advantage did the development of armour, shells, and exoskeletons provide to organisms during the Cambrian period?

Protection from predators and support against gravity (D) Signup and view all the answers

Increased CO2 and CH4 levels contributed to a major extinction event at the end of the Paleozoic era. Which of the following is a direct consequence of increased CO2 dissolved in seawater?

Lowered pH levels, harming organisms with calcium carbonate shells (D) Signup and view all the answers

What condition enabled oxygen to accumulate in Earth’s atmosphere during the Archean eon?

The binding of oxygen with iron, forming iron oxide, which allowed oxygen to enter the atmosphere (C) Signup and view all the answers

What key evolutionary innovation occurred during the Silurian period?

First jawed fish (C) Signup and view all the answers

How does heterochrony influence evolutionary change?

By changing the rate and timing of developmental events. (C) Signup and view all the answers

During which period did lush vegetation and coal swamps flourish, leading to significant coal deposits?

Carboniferous (C) Signup and view all the answers

What are the MAIN factors caused by the formation of the supercontinent Pangea during the Permian period?

Loss of shoreline habitat and increased competition (A) Signup and view all the answers

Flashcards

Scientific Methodology

A process for finding facts using tests and experiments, involving several steps from observation to hypothesis development.

Observation

The initial step in the scientific method, where data is gathered through the senses or instruments.

Hypothesis

A testable statement predicting the outcome based on observations in the scientific method.

Anthropocene

Current geological age viewed as the period during which human activity has been the dominant influence on climate and the environment.