Lizards are generally perceived as "unloving" parents, cause once the eggs are laid, the offspring are on their own. Yet, nature has again provided examples where species of lizards would form family groups. The article Lizards Have Family Values by O'Hanion describes the desert night lizards that group together under the logs are often genetically related, which can be proven through DNA analysis. This familial grouping also seem to coincide with lizards that have viviparity (live birth rather than egg-bearing), which results in fewer offspring that may live with longer lifespan. These desert night lizards do bear live offspring and tend to live long, as the subjects studied in the articles were found to be about 20 years old. Basically, these lizards are also playing the parent game in order to insure their species' survival, just like the other mammals and birds that are so different in physiology.
For me, I never heard of lizards actually forming family groups to care for young and each other (although one time I have heard that a group of related males worked together to obtain females and deterred other competition). Although the details weren't exactly clear on the exact behaviors involved (tested mostly on DNA of groups huddled during winter), it provides compelling evidences that a family system can be established. Even siblings could recognize each other! Since this was newly discovered, the actual interactions within a family system is not really known. Yet within a family system, there has to be some kind of communication just like in every family group. Do they communicate through a combination of movement, visual cues, sounds or pheromones? Do these communications further bond the family system? How does a lizard family group interact with each other? I am sure with future research that these questions would be answered, now that people know lizards can have a family just like us… just a cold-blooded one…
The Article: Lizards Have Family Values
Posted By: Leona Chan (Group A, Due:10/19/10)
Wow I had no idea lizards formed these family bonds! Along with all of your questions, it would be interesting to know if it's just the females that take care of the young, or if the males are present as well. Also, how long do the offspring stay with their parents? Eventually when they mate, do they go back to the same place they were born, or do they start a new family?
ReplyDeleteAbbie Lamarre-DeJesus
That's interesting. If most lizards do not have this family system, what caused this particular species to evolve differently? What could be the possible advantages, is it only for a longer life span?
ReplyDelete-Vince Tieu
This makes sense if it assures a longer lifespan for the lizard. Could this family relationship have anything to do with the lizards giving live birth? Could a hormone be released to trigger a type of parental response?
ReplyDelete-Kevin Tse
Thats really interesting! I love how much variation there can be in the strategies used by closely related animals! Do you know how many young the lizard usually has in one batch?
ReplyDelete-Lauren Lynch
I also have many questions about the lifestyle of these lizards. The article didn't provide the actual details of the lizards' activities, just confirmation of these family ties and what that would mean for other scientists and people. I think further research on the family interactions would be needed to answer all these questions about their lifestyles.
ReplyDeleteThe article does explain the correlation that seems to arise between social groups and viviparity. In the article, they mention that there is a species of lizards that would mate monogamously for 20 years, a sure sign that there is some kind of social ties. It seems that lizards that do give birth would have more advantage raising their offspring when there is some kind of family (minimum family members would be a male and a female) that work together. It would be interesting to trace the ancestors of some of these "social" lizards so we can see how maybe these family ties would have developed. Really, I think more research would help to answers all these questions!
-Leona Chan
that's so cool! Is there a point where the juveniles are on their own and have to form new groups (like primates kind of?) or how do they get new genetics into the group. It would be interesting to see if the group was welcoming f new individuals who aren't in the familial system.
ReplyDeleteHow long is the lifespan of the average lizard? Is it favorable for its survival to care for its young while possibly exposing itself to predation if its lifespan is indeed short??
ReplyDeleteAhmed Sandakli