Stages of life cycle of mammals

In summary, my buddy and I are arguing about the stages of life cycle for mammals. He says it should be three stages egg--> young--> adult and back. I say it should be two stages egg--> young--> adult. We are both pretty weak on this topic, so please help us. Thanks!
  • #1
dibilo
47
0
Dear experts, please help me with this debate between my buddy and I.

I'm on the side that most mammals, like cats, dogs, humans and monkeys have 2 stage life cycle. Young --> adult and back.

My buddy says it should be 3 stage egg--> young--> adult and back.

We are both rather weak on this topic. Please help. Thanks!
 
Biology news on Phys.org
  • #2
Hopefully some biologists will chime in with more insight, but on some level this is a moot.

You can define "stage" any way you want, and you will have as many stages as the definition will allow. You can have stages of life defined in biological terms - then between egg and young you can add morula, blastocyst, gastrula and some other and count them all. You can have stages defined in social terms - like childhood and adulthood - and you can count them again. You can also look at the stages of learning, of sexual life - each approach will give you different numbers.

Basically - you have to define what you mean first, and then you can start the discussion. Without a definition that you both agree on you are wasting time (doesn't mean you can't have a good time wasting time, that's a stage of life as well).
 
  • Like
Likes 1 person
  • #3
Quick post from my phone: borek is correct that in mammals it's pretty hard to draw any distinctive lines between stages of life. Unlike animals which undergo metamorphosis we don't change in radical spurts (I.e form cocoons). If you take the first 20 years of life a human obviously goes through a lot of development but its far more gradual. As for embryological development there are many, many stages defined by key events but that too is a gradual process.
 
  • #4
dibilo said:
My buddy says it should be 3 stage egg--> young--> adult and back.

Forgive my ignorance, but what is "back"?

I agree with Borek and Ryan, trying to tease out a life cycle for mammals isn't as clear cut as, say, doing the same for a butterfly, especially since there are thorny issues such as "neoteny" and "juvenalism" you have to sort through particularly when it comes to the primates. These issues are still very controversial in contemporary primatology, so you and your buddy are in good company.
 
  • #5
Human construct vs. metaphysics

Pre-script - Txs to Borek for the seed of this post's idea.

Hey, Discovering the truth about life cycles is interesting - but don't argue about what you call different stages, compare the facts, look at underlying truths in histology, endocrinology, embryology, population biology, etc. Remember that the stages we teach as current theory need to have human constructs in order to communicate. So we have terms for stages and we assign them based on recognizable current facts in morphology, embryology, evolution, etc.

If you're a current student, don't waste your time debating human constructs with fellow students - ask your prof. how she sees it and then regugitate that on the test. Outside of schoolwork and testing you can ask the important questions. Txs, Jack "Philosophy, Who Needs It?
 

What are the different stages of the life cycle of mammals?

The different stages of the life cycle of mammals are gestation, infancy, juvenile, adolescence, adulthood, and old age. These stages are marked by physical and behavioral changes that occur as the mammal grows and develops.

At what stage in the life cycle of mammals do they reproduce?

Mammals typically reproduce during adulthood, which is marked by sexual maturity. However, some mammals may also reproduce during adolescence, depending on the species.

How long does the life cycle of mammals typically last?

The length of the life cycle of mammals varies greatly depending on the species. Some mammals may only live for a few years, while others can live for several decades. On average, most mammals live for around 10-15 years.

What factors can affect the life cycle of mammals?

The life cycle of mammals can be affected by a variety of factors, including their environment, diet, and genetics. External factors such as climate change, pollution, and human interference can also impact the longevity of mammal species.

Do all mammals go through the same stages in their life cycle?

No, not all mammals go through the same stages in their life cycle. Some mammals may have longer gestation periods, while others may have shorter periods of infancy or old age. Additionally, the length of each stage can vary greatly between different mammal species.

Similar threads

  • Biology and Medical
Replies
1
Views
2K
  • General Discussion
Replies
4
Views
1K
  • Sci-Fi Writing and World Building
Replies
7
Views
1K
  • Biology and Medical
Replies
8
Views
2K
  • Sci-Fi Writing and World Building
3
Replies
87
Views
4K
  • Biology and Medical
Replies
6
Views
2K
Replies
60
Views
6K
  • Sci-Fi Writing and World Building
Replies
6
Views
545
  • Science Fiction and Fantasy Media
Replies
3
Views
2K
Replies
16
Views
2K
Back
Top