【Native Speaker每日综合训练—38系列】【38-01】科技 de-extinction

cyndichiang

Speaker:
Technology can prevent extinction by putting the notion of de-extinction and using synthesis of DNA

Time2 2'20''
The problem is whether should we clone extinct creatures,not how to clone them

Time3 1'26''
Mammoths  are similar to current elephants in aspects such as habitats, eating habits and group behaviors

Time4 1'18''
Even though scientists can indicate the diets and habitats of mammoths, many other related problems are hard to solved,such as whether mammoths can survive in today's environment.

Time5 1'35''
The author thinks that the clone of mammoths is meaningless and he raises many problems to clone a mammoths. Then he said that there are many reasons to reconstruct some species but the development of the eco-community is cascading.

Time6 2'09''
The author fight against the de-extinction because he thinks that the reconstruction of a specie is cascading effect and this effect is new area just like the exploration of moon.
The author also thinks that the clone of mammoths is not urgent and such reconstruction spends far more resources than expected.
Last, he points out that protecting pre-extinction species is more significant than de-extincting.

Obstacle: 4'42''
Even though the clone is feasible to preserve the endangering species and to de-extinct, the success rate is still small.
There are three major problems faced by scientist when cloning:
Some scientists are figuring out, but these attempts are established upon the deaths of cats and dogs

NativeStudy菌

行者无疆945 发表于 2014-6-16 22:44
新一期~要加油啊！

Hey, man~
you should work harder and quicker~~~ it's been 2 days and your seat is still blank~ hope you remember to fill it!
have a good day!

viennall

Spreaker
Scientists got sample of extinced animals from the museum and collected the DNA to make copy and prevent the extinction in first place.

Speed
00'51 As on ecologist, I will never look my study oganisms in the eye. As a conservation p, I study the natural experiments of the past.
02'48 De-extinction will solve the problem. The de-extinction proposals are big ideas, which need careful consideration.
01'49 The cloning of the woolly mammoth is likely to be one of the most successful cloning efforts. The mammoths' habitat is alone and they have similar social system as modern elephants.
02'52 We know all the information from the fossils. Not all teenaged mammoths survived the dangerous period of isolation. Mammoths have low frequency communication.
02'22 Human activity is pushing the earth system outside of the natural range of climate variability that mammoths have experienced. There are compelling ecological reasons to resurrect extinct species.
02'26 Cloning extinc species may actually be more about us humans than the wildlife we care about. Arguments against de-extinction often center round what we don't know. The cloning doesn't end in the lab.


obstacle
07'14

Main idea: It needs more efforts on Cloning to save endangerd life.
Structure:
A Brazilian corporation collected the DNA from endangered wildlife in order to clone the endangered animals with 1 percent successful.
At present, cloning is not a feasible or effective consevation strategy.
Cloning does not address the reasons that many animals become endangered in the first place.
Successful cloning generally involves at least three essencial components: DNA, viable egg, mother.
Although there are many problems for these, efforts to archive the genetic information of endangered wildlife is worthwhile.
Cloning is unlikely help the white rhino or any other threatened species.
The mismatch is the fundamental problem for all the clonings:
Not exact replicas.
Unusual hybrid embryo.
Unusual nuclear transfer.
Scientists figure out how to encourage nuclear reprogramming.
Some of the most attempts for cloning is dogs and cats.

crystal9291

obstacle 10:55
Researchers want to use cloning technique to conserve endangered species, but they face many problems:
1 hybrid embryos often fail to develop
+:cloning is a promising tool to save endangered species.
e. rhinoceros

! cloning does not make a difference nowadays

**the clones species died for different reasons:
they are derived from combined DNA(legal limits, poor understanding of reproductive physiology of endangered animals)
**hybrid embryos fail to develop because the proteins do not fit together and the surrogate mother may refuse the foreign embryos

2 incomplete nuclear reprogramming

solutions:
1 to nurture a hybrid embryo in the lab at first-->transplant cell mass to T-->less rejection to T
2 to encourage nuclear reprogramming by bathing the egg in compounds and chemicals
3 replace the egg's native mtDNA with that from the species to be cloned

无悔y哥

A genetic tech to bring back extinction species
00:51' I can't see my experimental animals any more
01:42' the question whether we should de-extinct mammoths is more important than how we can de-extinct them.We should take habitats, foods, resources ect into consideration.
02:03' the mammoth is the first successful coloning effort.By dicovering its body, we know it is most like an elephant eating herb and grass and becoming marital.
02:50' we can get the information about water,food mammoth eat from fossils and isotops.
02:05' the historical environment is different from now,which may cause a problem for mammoths.
02:27'many people are against de-extinction .I dream to see mammoths again because of TV series saw in childhood. It is not urgent to colony them but to care for exist big animals .We should focus on pre-extinction.
10:57'  colonying endangered animals isn't very successful.many scientists collect many types of genes for future colonying.  the tech isn't effective.We need insert genes in an egg,but this may cause mismatch.

行者无疆945

主页菌 发表于 2014-6-19 09:35
Hey, man~
you should work harder and quicker~~~ it's been 2 days and your seat is still blank~ hop ...

菌菌，我昨天有提交作业！在29楼！只是我忘记之前在主页take a seat了，然后就在后面提交了...以后我会注意的！Have a nice day~

NativeStudy菌

行者无疆945 发表于 2014-6-20 00:01
菌菌，我昨天有提交作业！在29楼！只是我忘记之前在主页take a seat了，然后就在后面提交了...以后我会注 ...

Ok! Thanks for your remind~ Don't make it happen next time~
Have a good day!

happyxgb

Warm up: As a paleoecologist, I study organisms not from seeing, but from natural experiments of past such as extinction and climate change.
Time 2: 01:45 De-extinction could recurring the extinct species for conservation.  While the concept of colon is misleading, there are strong clues to ecology.
Time 3: 02:15 Mammoths fossils are the most complete specimens.  They lived in a very wide range.  What we can know now are their eating habits--that most of them were grazers, their habitat, and their social system, which was matriarchal.  
Time 4: 02:49 Mammoths had rings on their tusks, which indicate that male mammoths were isolated when they got adolescence.  However, not all young adults survived in the isolation.  Evidences show that mammoths were similar to modern elephants in communication systems.  Questions of how many of them in the wild were not known but they were very easily threatened when climate changed.
Time 5: 02:31 Speaking of clone mammoths, what is woolly mammoth?  It is definite that single mammoth is not a real mammoth.  The natural climate is out of the range that mammoth would have faced.  Even though there are several reasons for recurring the species.  But the extinct species created novel communities that led to the modern elephants.
Time 6: 02:43 is our society prepared to accept the de-extinction?  The understandable impetus just benefits people more than wildlife.  Scientists go against the de-extinction because of the unknown long-term effects, no hurry of cloning and no ending track records.  What is important is that applying how woolly mammoths saved the species.  
Obstacle: 10:51 Many scientists began freezing sperms of wild animals to preserve them.  However, success were less than failures.  Cloning is known as an ineffective strategy and faces several impediments.  Cloning involves complicate DNA factors and faces legal protection and genetic failure.  While some scientists think the technology is worth improving.  One example of white rhinoceros proves the benefits.  However, the coloring is unlikely help the endangered species for most of the hybrid died.  The shared problem is that the hybrid is not the exact replica.  There is mismatch, which lead to another problem---the incomplete nuclear reprogramming.  Some ways offer better chances of living and encourage reprogramming.   The most successful attempts have involved two domestic species

leo688

Part I: Speaker

De-extinction, a method for getting the whole DNA for extinct species, could be a way to bring back ancient species.

[Warm up]

The author, as an ecologist, is never observe the research objectives since the available fragments could account for only a part the whole picture once there.

[Time 2]

De-extinction could clone the already exited animal, such as woolly mammoth, but related questions has to be answered before conducting the revival work. For instance, what does it mean to be a mammoth? how to maintain the ecology environment without impact on current ecosystem?

[Time 3]

The introduction of mammoths' category, habits, society, and some comparison with current elephant.

[Time 4]

Some studies about mammoth's fossil show that the animal's chronological nutrition patterns, and heritage requirement, and some reappearing of their daily life. But it is still hard to know much the overall heritage required to reappear the nature survival.

[Time 5]

To dig deep the root cause for recovering some ancient animals, such as mammoths. The more consideration should focus on the whole ecosystem instead of the individual piece.

[Time 6]

The complex discussion about the clone of individual piece and of the whole related living content do not allow de-extinct mammoth, and the higher priority of implementing the technology is to help current pre-extinctive species.

Obstacle

[warm up]

Two Brazilian scientists began scavenging and freezing blood, sperm and umbilical cord cells of some endangers species as a potential makeup DNA resource for future extinction. Current successful cloning rate is still lower than 5%.

[Paraphrase 7]

Using clone to save the threatened species has a long way to go: the low successful rate of clone and related reasons.

wensd1111

1 A 00:59
2 A 02:06
3 A 02:21
4 A 02:56
5 A 02:40
6 A 03:29
7 A 01:15
8 A 09:48
clone might endanger the species. successful clone require 3 neccesaties. one of them is poorly understand, so the clone often failed. the second part, the two direct reason affect clone. one is in-, the other the embrye do recognise outsider as foreigner. two ways could improve the incidence of successful, bathing and prolonged grown.