R version 3.3.3 (2017-03-06) -- "Another Canoe"
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Platform: x86_64-apple-darwin13.4.0 (64-bit)

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> SynoData <-read.table("~/Desktop/SynoData.csv",header = TRUE, sep = ",")
> mod1 <- aov(Jaw~Notochord*Species, data = SynoData)
> summary(mod1)
                  Df Sum Sq Mean Sq  F value  Pr(>F)    
Notochord          1 16.505  16.505 4713.590 < 2e-16 ***
Species            1  0.090   0.090   25.746 1.2e-05 ***
Notochord:Species  1  0.009   0.009    2.466   0.125    
Residuals         36  0.126   0.004                     
---
Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
> mod2 <- aov(Jaw~Notochord+Species, data = SynoData)
> summary(mod2)
            Df Sum Sq Mean Sq F value   Pr(>F)    
Notochord    1 16.505  16.505 4533.93  < 2e-16 ***
Species      1  0.090   0.090   24.77 1.52e-05 ***
Residuals   37  0.135   0.004                     
---
Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
> anova(mod1,mod2)
Analysis of Variance Table

Model 1: Jaw ~ Notochord * Species
Model 2: Jaw ~ Notochord + Species
  Res.Df     RSS Df  Sum of Sq      F Pr(>F)
1     36 0.12606                            
2     37 0.13470 -1 -0.0086357 2.4662 0.1251
> multipunctatus <- subset(SynoData, Species=="Sm")
> lucipinnis <- SynoData[SynoData$Species=='Sl',]
> reg1 <- lm(Jaw~Notochord, data=multipunctatus); summary(reg1)

Call:
lm(formula = Jaw ~ Notochord, data = multipunctatus)

Residuals:
      Min        1Q    Median        3Q       Max 
-0.152795 -0.040280  0.009648  0.049943  0.115375 

Coefficients:
            Estimate Std. Error t value Pr(>|t|)    
(Intercept)  0.04942    0.41826   0.118 0.907244    
Notochord    0.22082    0.04748   4.650 0.000199 ***
---
Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1

Residual standard error: 0.07308 on 18 degrees of freedom
Multiple R-squared:  0.5458,	Adjusted R-squared:  0.5205 
F-statistic: 21.63 on 1 and 18 DF,  p-value: 0.000199

> reg2 <- lm(Jaw~Notochord, data=lucipinnis); summary(reg2)

Call:
lm(formula = Jaw ~ Notochord, data = lucipinnis)

Residuals:
      Min        1Q    Median        3Q       Max 
-0.039809 -0.021196 -0.015447  0.001653  0.122536 

Coefficients:
            Estimate Std. Error t value Pr(>|t|)    
(Intercept)  0.07949    0.15429   0.515 0.612714    
Notochord    0.12760    0.03117   4.094 0.000682 ***
---
Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1

Residual standard error: 0.04078 on 18 degrees of freedom
Multiple R-squared:  0.4821,	Adjusted R-squared:  0.4534 
F-statistic: 16.76 on 1 and 18 DF,  p-value: 0.0006819

> plot(Jaw~Notochord, data=SynoData, type='n')
> points(multipunctatus$Notochord,multipunctatus$Jaw, pch=20)
> points(lucipinnis$Notochord,lucipinnis$Jaw, pch=1)
> abline(reg1, lty=1)
> abline(reg2, lty=2)
> legend("bottomright", c("S. multipunctatus","S. lucipinnis"), lty=c(1,2), pch=c(20,1))