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Course: Middle school biology - NGSS > Unit 8
Lesson 4: Evidence of evolution: embryologyEvidence of evolution: embryology
Review your understanding of embryological evidence of evolution in this free article aligned to NGSS standards.
Key points
- Embryos are unborn or unhatched organisms early in the course of development.
- Embryos grow and develop in a series of stages. During this growth, an embryo’s physical features change. Some features get more specialized. Other features disappear.
- Embryos of different species can have similarities that are not visible when the organisms are fully formed. Many of these similarities are homologous features. These features provide evidence that the species are related through evolution.
- For example, all embryos have homologous structures called pharyngeal arches, or gill arches. In fish, these arches develop into parts of the gills. In mammals, these arches develop into parts of the ears and jaw.
- In general, embryos of related species have more features in common at earlier stages of development than they do at later stages.
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So the embryo of a human can be viewed when doctor's view a child before it's born?(16 votes)
A human embryo transitions to being a fetus at somewhere between 8 and 12 weeks of pregnancy. The human organism itself (as opposed to the gestational sac) may not be visible until somewhere between 6 and 10 weeks, so you may only see the human when they are a fetus instead of an embryo.(18 votes)
This looks similar to babies in a human stomach. Do they actually have that many similarities?(6 votes)
If you look at different mammals and birds when they are still embryos, you will find that they are quite similar. However, these similarities stop as the embryos keep developing. By the time a baby is born, it looks different from an embryo.(15 votes)
Aren't living creatures just fascinating? All of us can feel emotions, Humans can form complex relationships, Languages and build structures from the resources around us, Other animals can do similar things, It makes you wonder what it would be like if other creatures evolved like this instead of humans, What would we be like to them? How would they look? Act? What would happen if say, We evolved from birds? Would we fly around and create taller structures as opposed to the ones we make? How would it effect our ways of living? Would we have created planes? How would our digestive systems work, Evolution really makes one wonder, Doesn't it?(13 votes)- not facinating(0 votes)
- so all humans and animals have an Embryo and which animals don't have one?(5 votes)
all animals develop from one.(8 votes)
i wish i had a tail...(4 votes)
do animals get bigger or smaller(3 votes)- animals tend to get bigger as they grow.(2 votes)
I wonder why our "tail" falls off whenever we reach 8 weeks when we are a embryo(0 votes)
They don't fall off, they just move position to make up the bottom of your spine, also called your tail bone.(6 votes)
- As time go on do they grow to ther max size?(3 votes)
Yes you can see that with humans as well as all species in the kingdom fauna!(2 votes)
- How can i get my tail back(3 votes)
Typically when do you start to notice changes in development?(3 votes)
