Bio accumulation of DDT lead to bird eggs with weak shells and non viable offspring. The lethal effects of DDT on birds was first noted in 1950; scientists discovered that earthworm was accumulating the DDT pesticide and that the robins that were preying on the earthworms were been poisoned. Further research revealed that the chemical cause thinning of the egg shell and production of non viable offspring. The chemical has since been banned in USA.
The provided question is incomplete, the correct and complete question is as follows:
Choose the answer that best completes the sentence below.
Scientists group materials together ____________ it is easier to compare and study them that way.
A however
B but
C although
D because
Answer:
The correct answer is - option D because.
Explanation:
Researcher and scientists tries to group material together on their similarities and difference to one another which makes it easier to study and compare various type of materials.
It is the one of major reasons to differentiate materials between groups like liquids state, gases state, plasma state and solid state materials. One can easily see the difference and comparison is very clear on this type of grouping of materials.
Thus, the correct answer is - option D.
Phosphate
Because it is the group of the molecules
The best answer is: introducing exotic species into
<span>
new environments. This can be actually bad, as new species can actually reduce the biodiversity in the environments to which they're introduced</span> , such when cats hunt indigenous birds.
I was a bit thinking about the last option too: making sure local people benefit from conservation efforts.
This is not one of the classical goals of the conservation efforts, but since the previous one is definitely correct, i don't this one is. (it's not that it's not a goal, but it isn't a main focus)
Answer:
The platypus serves as a 'bridge' animal between nonmammals like birds and reptiles, which maintain their testicles in their body cavity, and placental and marsupial mammals, which hold their testes in an external scrotum."