subject
Biology, 09.12.2020 22:20 baca23jasmine

Will mark brainliest if answers are correct read the article ( Adapted from: How a Curious Mammal Evolved Its Venom- The New York Times
By Veronique Greenwood Dec. 1, 2019
Solenodons are highly unusual, and very difficult to study
The Hispaniolan solenodon is a wondrously strange creature.

About the size of a guinea pig, it has a long, hairless snout, sharp little teeth and, to top it all off, venom-laced saliva. Highly endangered, it lives in the forests of the Dominican Republic and Haiti, and scientists have had to work hard to understand its habits and evolution. But in a paper published Tuesday, a diverse group of researchers outline the intriguing conclusions they reached about how the solenodon got its dangerous spit, after they sequenced its DNA and analyzed its venom.

It was not easy finding solenodons to study, said Nicholas Casewell, a venom expert and a co-author of the new paper. The team managed to track down two of the animals in the wild. At the National Zoological Park in the Dominican Republic, they took blood for DNA sequencing from a captive solenodon — one of the only captive specimens in the world. They compared the DNA of the soledon to those of related animals, like hedgehogs, moles and shrews, and identified substances present in the venom, including a set of molecules called kallikreins.

Kallikreins chop up other proteins, including some that help maintain blood pressure. The researchers injected mice with solenodon venom and saw that indeed, while their pulse and breathing did not change, their blood pressure dropped dangerously as soon as the venom went in. This could make prey foggy-headed and easier for the solenodon to finish off, the researchers suggest.

Another venomous mammal among the solenodon’s relatives, the northern short-tailed shrew, also has kallikreins in its venom.
“To us, it was a real surprise to find very similar proteins in the venom of the solenodon and shrews,” Dr. Casewell said.

They asked whether venom might have existed in the common ancestor of moles, hedgehogs, shrews and solenodons. But if a common ancestor did have this trait, an improbably large fraction of its descendants would have had to mysteriously lose it for the modern family tree to make sense.

The researchers concluded that it is more likely that shrews and solenodons came up with the adaptation after they branched off from these other small mammals. They think the trait is likely to have evolved independently in each animal, as shrews and solenodons do not use the exact same kallikreins in their venom as shrews.

But the fact that there is an overlap in these molecules in two different animals implies that mammals have very limited options to work with when it comes to developing a venom. Kallikreins are commonly present in mammal saliva, so modifying them little by little to get something more dangerous is a plausible route for venom’s evolution.

The researchers wonder, however: Are solenodons still using their venom? The last 500 years have seen the extinction of many prey species, like lizards, birds and other vertebrates, on their home island. This ecological destruction has left behind mainly insects, which may not be affected by the venom.

Dr. Casewell and his colleagues hope that future observations of wild solenodons on the hunt may provide insight into whether its unusual venom is still useful to solenodons in their daily lives, or if it is a relic of a time, and an ecosystem, that no longer exists.)

and answer the question

a) what is the authors claim?

b) summarize 2 pieces of evidence from the article

c) explain how the evidence supports the claim?

d) summarize final piece of evidence) and explain how the evidence spports the claim?

e) What is one weakness in the research?

f) According to the article, and your understanding of evolution, would the venom in the saliva of the solenodon be considered a homologous trait or an analogous trait. Explain your answer.

ansver
Answers: 1

Another question on Biology

question
Biology, 21.06.2019 15:40
Aneuron is stimulated with an electric pulse. the action potential is detected at a point 3.70 cm down the axon 0.0052 s later.when the action potential is detected 7.20 cm from the point of stimulation, the time required is 0.0063 s. what is the speed of the electric pulse along the axon? (why are two measurements needed instead of only one? )
Answers: 2
question
Biology, 22.06.2019 03:30
Which statement best describes a typical difference that could be found between the "analysis" and "conclusion" sections of a lab report? a) only the "conclusion" describes errors that occurred during the experiment, and only the "analysis" section suggests further research.b) only the "analysis" section includes specific data comparisons, and only the "conclusion" section suggests further research.c) only the "analysis" section discusses whether the original hypothesis was supported, and both sections include graphs of data.d) only the "conclusion section discusses whether the original hypothesis was supported, and both sections suggest further research.(the answer is b i just took the test)
Answers: 1
question
Biology, 22.06.2019 04:10
Select the correct answer. tay-sachs disease is caused by a mutation in the hexa gene located on chromosome 15. tay-sachs follows an autosomal recessive pattern of inheritance. with the of the diagram, identify which of the offspring will be an unaffected carrier. a diagram showing the genes of parents who are carriers of tay-sachs disease a. a, b, and c b. b and c c. a and d d. a e. d
Answers: 3
question
Biology, 22.06.2019 04:30
Why are scientists concerned about the depletion of the ozone levels in the stratosphere?
Answers: 2
You know the right answer?
Will mark brainliest if answers are correct read the article ( Adapted from: How a Curious Mammal E...
Questions
question
Health, 29.07.2019 14:50